Engineering and Technical
Services for Joint Group on
Acquisition Pollution
Prevention (JG-APP) Pilot
Projects
Potential Alternatives Report
HM-A-1-1
Alternatives to Chrome
Conversion Coatings on
Aluminum Alloys 2024, 6061,
7075, and Ion Vapor Deposited
Aluminum on Steel
January 29, 1998
Contract No. DAAA21-93-C-0046
Task No. N.072
CDRL No. A004
Prepared by:
National Defense for Environmental Excellence (NDCEE)
Operated by Concurrent Technologies Corporation (CTC)
Engineering and Technical Services for
Joint Group on Acquisition Pollution
Prevention (JG-APP) Pilot Projects
Potential Alternatives Report
HM-A-1-1
Alternatives to Chrome Conversion Coatings
on Aluminum Alloys 2024, 6061, 7075, and
Ion Vapor Deposited Aluminum on Steel
January 29, 1998
Distribution Statement "A" applies.
Approved for public release; distribution is unlimited.
Contract No. DAAA21-93-C-0046
Task No. N.072
CDRL No. A004
Prepared by:
National Defense for Environmental Excellence (NDCEE)
operated by Concurrent Technologies Corporation (CTC)
1450 Scalp Avenue
Johnstown, PA 15904
TABLE OF CONTENTS
Page
PREFACE .....................................................................................................................................iii
EXECUTIVE SUMMARY.......................................................................................................... iv
1. INTRODUCTION............................................................................................................. 1
2. BASELINE PROCESS ..................................................................................................... 3
2.1. Baseline Process Flow............................................................................................. 3
2.2. Baseline Process Description .................................................................................. 4
2.3. Baseline Process Equipment ................................................................................... 6
2.4. Baseline Material and Energy Usage....................................................................... 6
2.5. Baseline Waste and Emissions Summary ............................................................... 6
2.6. Environmental, Safety, and Occupational Health (ESOH) Status for the Baseline
Process..................................................................................................................... 7
2.6.1. Environmental Issues .................................................................................. 7
2.6.2. Health and Safety Issues.............................................................................. 8
2.7. Baseline Capital and Operating Costs ................................................................... 10
3. IDENTIFIED ALTERNATIVES AND PRELIMINARY SCREENING .................. 12
3.1. Alternative Technology Selection ......................................................................... 12
3.2. Product Identification ............................................................................................ 14
3.2.1 Technical Criteria...................................................................................... 15
3.2.2. Environmental Criteria.............................................................................. 16
3.2.3. Health and Safety Criteria ......................................................................... 16
3.2.4. Commercial Availability ........................................................................... 16
3.3. Preliminary Technical Screening of Identified Alternatives ................................. 18
3.3.1. Alcoat 4000 ............................................................................................... 23
3.3.2. Alodine 2000 ............................................................................................. 23
3.3.3. Alumicoat 6788 ......................................................................................... 23
3.3.4. Alumitec .................................................................................................... 24
3.3.5. Chemcote L497260A ................................................................................ 24
3.3.6. Chrome-Free Conversion Coating (CFCC)............................................... 25
3.3.7. Sanchem FP (Full Process) ....................................................................... 26
3.3.8. Sulfuric-Boric Acid Anodizing (SBAA)................................................... 26
3.3.9. Summary ................................................................................................... 27
4. PROCESS DESCRIPTIONS FOR VIABLE ALTERNATIVES ............................... 28
5. PRELIMINARY ESOH ANALYSIS OF VIABLE ALTERNATIVES ..................... 30
5.1. Environmental Issues ............................................................................................ 30
5.2. Safety and Occupational Health Issues ................................................................. 30
6. SELECTION OF POTENTIAL ALTERNATIVES.................................................... 34
7. SUMMARY...................................................................................................................... 35
Potential Alternatives Report i
LIST OF FIGURES
Page
Figure 1. Flow of Baseline Chrome Conversion Coating Process ......................................... 4
LIST OF TABLES
Table 1. HMSC Target HazMat Summary............................................................................ 2
Table 2. Steps of Baseline Chrome Conversion Coating Process ......................................... 5
Table 3. Chemicals in Baseline Conversion Coating Process and Worker Exposure
Limits ...................................................................................................................... 9
Table 4. Annual Costs for Baseline Chrome Conversion Coating...................................... 11
Table 5. Most Viable Alternatives to Chrome Conversion Coating ................................... 12
Table 6. Identified Alternative Technologies to Chrome Conversion Coating.................. 13
Table 7. Identified Alternative Products to Chrome Conversion Coatings......................... 14
Table 8. Key Characteristics of the Identified Chrome Conversion Coating Alternatives . 17
Table 9. Chrome Conversion Coating Alternatives ?Existing Performance Data ............. 21
Table 10. Screened List of Alternative Products................................................................... 22
Table 11. Historical Test Results for Alcoat 4000 ................................................................ 23
Table 12. Historical Test Results for Alodine 2000.............................................................. 23
Table 13. Historical Test Results for Alumicoat 6788.......................................................... 24
Table 14. Historical Test Results for Alumitec..................................................................... 24
Table 15. Historical Test Results for Chemcote L497260A ................................................. 25
Table 16. Historical Test Results for CFCC.......................................................................... 26
Table 17. Historical Test Results for Sanchem FP................................................................ 26
Table 18. Historical Test Results for SBAA ......................................................................... 27
Table 19. Viable Alternatives to Chrome Conversion Coating............................................. 27
Table 20. Process Parameters for Viable Alternatives .......................................................... 28
Table 21. Summary of ESOH Analysis for Viable Chrome Conversion Coating
Alternatives ........................................................................................................... 33
Table 22. Potential Alternatives to Baseline Chrome Conversion Coating .......................... 34
=
LIST OF APPENDICES
Appendix A. Technology Survey to Identify Potential Alternatives
Appendix B. Product Identification
Appendix C. Preliminary ESOH Analysis of Viable Alternatives
Appendix D. References
=
Products and companies mentioned here may be the trademarks of their respective owners.
ii Potential Alternatives Report
PREFACE
This report was prepared by Concurrent Technologies Corporation (CTC) through the National
Defense Center for Environmental Excellence (NDCEE) under Contract Number DAAA21-93-
C-0046. This report was prepared on behalf of, and under guidance provided by the Joint Group
on Acquisition Pollution Prevention (JG-APP) through the Joint Pollution Prevention Advisory
Board (JPPAB). The structure, format, and depth of this report's technical content were
determined by the JPPAB, Hughes Missile Systems Company (HMSC), and government
technical representatives in response to the specific needs of this project.
Invaluable technical, business, and programmatic contributions were provided by the
organizations listed below.
Advanced Medium Range Air to Air Missile Program Office (AMRAAM)
Aeronautical Systems Center, Environmental Management Office (ASC/EM)
Air Force Corrosion Program Office
Air Force Materiel Command (HQ AFMC/DRIE)
Air Force Research Laboratory ?Materials Laboratory
Air to Ground Missile Systems Program Office (AGMS)
Army Materiel Command, Headquarters (AMC HQ)
Chief of Naval Operation, Environmental Programs Division
Close Combat Anti-Armor Weapon System Program Office (CCAWS)
Comanche Program Office
Cruise Missile Program Office
Defense Contract Audit Agency (DCAA)--Hughes, Tucson
Defense Contract Management Command (DCMC)-- Hughes, Tucson
Defense Contract Management District West (DCMDW/DACO)
Defense Logistics Agency, Headquarters (HQ DLA)
Hughes Missile Systems Company (HMSC)
Industrial Operations Command, Headquarters (HQ IOC)
Joint Depot Environmental Panel
Lead Maintenance Technology Center for the Environment (LMTCE)
National Aeronautics and Space Administration (NASA)
National Defense Center for Environmental Excellence (NDCEE)
Naval Air Warfare Center--China Lake
Naval Air Warfare Center--Lakehurst
Naval Aviation Depot--Cherry Point
Naval Facilities Engineering Service Center (NFESC)
Navy Air Systems Command, Shore Station Management (NAVAIR Code AIR 8.0Y4)
Ocean City Research Corporation (OCRC)
Program Executive Office, Theater Air Defense (PEO TAD)
Stinger Program Office (MICOM)
Tomahawk Program Office
Potential Alternatives Report iii
EXECUTIVE SUMMARY
Chrome conversion coating involves the treatment of a metal substrate with a chrome solution to
produce an adherent coating. The metal substrate is changed to a layer of chromium salts to
produce the desired decorative or functional properties. Chrome conversion coatings are used for
three general purposes:
? Increase corrosion resistance
? Improve paint (primer) adhesion
? Minimize electrical resistance.
Although chrome conversion coating offers many advantageous coating properties, its use of
hexavalent chromium is strictly regulated due to the compound's toxicity and suspected
carcinogenicity. For this reason, manufacturers have begun to identify, evaluate, and implement
acceptable alternatives for chrome conversion coating where feasible. These alternative
technologies commonly generate less pollution than chrome conversion coatings and have fewer
associated health and safety risks.
At the Hughes Missile Systems Company (HMSC), Tucson, Arizona, a Joint Group on
Acquisition Pollution Prevention (JG-APP) project site, chrome in chemical conversion coatings
was identified as a hazardous material of concern, and targeted for elimination or reduction.
HMSC uses chrome conversion coatings in its production of tactical missile systems, and related
equipment for use in air, land, and sea defense applications. The corresponding substrates that
are coated at HMSC are aluminum alloys 2024, 6061, and 7075, and aluminum deposited on
steel by ion vapor deposition.
This Potential Alternatives Report (PAR) provides an analysis of identified alternatives to
chrome conversion coating and recommended alternatives for testing and possible
implementation at HMSC.
Twenty potential alternatives to chrome conversion coatings were identified in November 1995
through literature searches and direct vendor queries. Four of these identified alternatives were
classified as technically viable based on available information. These viable alternatives were
Alodine 2000, Alumicoat 6788, Chrome-Free Conversion Coating (CFCC), and Sanchem FP.
The environmental, safety, and occupational health characteristics of these viable alternatives
were evaluated. In addition, the key process characteristics of these alternatives were compared
to those of the existing process. As a result of the analyses, all four of these alternatives were
classified as potential alternatives and chosen for testing in accordance with the approved Joint
Test Protocol for the Validation of Alternatives to Chrome Conversion Coatings for Aluminum
Alloys 2024, 6061, 7075, and Ion Vapor Deposited Aluminum on Steel, dated May 21, 1996.
Test results are then reported in the Joint Test Report for the Validation of Alternatives to
Chrome Conversion Coatings for Aluminum Alloys 2024, 6061, 7075, and Ion Vapor Deposited
Aluminum on Steel.
iv Potential Alternatives Report
1. INTRODUCTION
On September 15, 1994, the Joint Logistics Commanders (JLC) chartered the Joint Group
on Acquisition Pollution Prevention (JG-APP) to coordinate joint service activities
affecting pollution prevention issues identified during a defense system's acquisition
process. The primary objectives of the JG-APP are to:
? Reduce or eliminate the use of Hazardous Materials (HazMats)
? Avoid duplication of efforts in actions required to reduce or eliminate
HazMats through joint service cooperation and technology sharing.
The focus of JG-APP is on contractor design, manufacturing, and remanufacturing
locations, with transfer of technology to the Sustainment Community.
To reduce HazMats, the JG-APP process first identifies the HazMat, related process, and
affected substrates or parts at an original equipment manufacturer (OEM) facility. Details
identified include equipment requirements; material and energy usage; waste and
emission generation; environmental, safety, and occupational health (ESOH) issues; and
capital and operating costs. This information is provided by the OEM and is documented
in a Potential Alternatives Report (PAR) (refer to Section 2).
Identifying and selecting alternative processes that have the potential to reduce the
identified HazMats can be a complicated task due to the fast pace at which new
technologies emerge, and the ever-increasing volume of published and unpublished
documentation. In the JG-APP process, a technology survey is performed to identify
commercially available or near commercially available alternative technologies. The
alternatives are identified through literature searches, electronic database searches,
Internet searches, customized surveys, and/or personal and professional contacts. The
technology survey, which is documented in the PAR, serves as a foundation for the
remainder of the PAR and for selection of alternative processes (refer to Appendix A).
After reviewing technical and ESOH information in the technology survey, project-
related U.S. Department of Defense (DoD) and OEM technical representatives select a
shortened list of viable alternative technologies. The selection rationale and conclusions
are documented in the PAR, and vendors of the selected technologies are contacted
concerning their specific products. DoD and OEM technical representatives then select a
shortened list of vendor products to be further considered, based on information in the
PAR (refer to Section 3 and Appendix B).
The identified vendor products then undergo a more in-depth technical and preliminary
ESOH analysis. The technical analysis includes determining how well the alternatives
match the OEM's operations and future needs. Examples of evaluation criteria may
include expected additional equipment, material and energy usage, waste and emission
generation, and capital and operating costs (refer to Section 4). The preliminary ESOH
analysis provides an initial qualitative assessment of viable alternatives, identifying
Potential Alternatives Report 1
conspicuous ESOH issues that may be a factor when selecting an alternative to the current
process (refer to Section 5).
After reviewing the technical and ESOH analyses, DoD and OEM technical
representatives jointly select potential alternatives for testing in accordance with the Joint
Test Protocol for the Validation of Alternatives to Chrome Conversion Coatings for
Aluminum Alloys 2024, 6061, 7075, and Ion Vapor Deposited Aluminum on Steel, dated
May 21, 1996, developed for the OEM (refer to Section 6). Test results are reported in
the Joint Test Report for the Validation of Alternatives to Chrome Conversion Coatings
for Aluminum Alloys 2024, 6061, 7075, and Ion Vapor Deposited Aluminum on Steel.
This PAR has been developed for the Hughes Missile System Company (HMSC),
Tucson, Arizona. At this site, chrome in chemical conversion coatings was identified as
the target HazMat to be eliminated or reduced. HMSC uses chrome conversion coatings
in its production of tactical missile systems and related equipment for use in air, land, and
sea defense applications. Chrome conversion coatings are used to increase corrosion
resistance, improve paint (primer) adhesion, and increase the resistance to corrosion while
minimizing electrical resistance. The substrates involved are aluminum alloys 2024,
6061, and 7075, and aluminum deposited on steel by ion vapor deposition. Table 1
summarizes the target HazMat, process and material, applications, current specifications,
affected programs, and candidate substrates.
Table 1. HMSC Target HazMat Summary
Target Process/ Current Affected Candidate
HazMat Material Applications Specifications Programs Substrates
Chemical ?Corrosion ?Aluminum
Chrome - MIL-C-5541 Navy: Std
7,850 lb/yr Conversion Resistance MIL-C-81706 Missile, Alloys
?Paint
Coatings Phalanx, 2024, 6061,
RAM, 7075
Adhesion
?Ion Vapor
?Electrical Tomahawk
Air Force: Deposition
Resistance
ACM, of
AMRAAM Aluminum
Army: on Steel
TOW,
Stinger
2 Potential Alternatives Report
2. BASELINE PROCESS
The present chrome conversion coating process used at the identified HMSC site is
located in Building 814, which is also Air Force Plant 44. The process has eight steps,
excluding part cleaning (aqueous clean and rinse), loading, and unloading. The following
baseline information was provided by HMSC.
The current process used to provide low to moderate resistance to corrosion of aluminum
surfaces is described in Military Specification (MIL SPEC) MIL-C-5541 (Chemical
Conversion Coatings on Aluminum and Aluminum Alloys, issued November 30, 1990).
This process involves applying a series of aqueous solutions to the metal parts. Some of
these solutions contain chromated and other inorganic salts. A thin, nonelectrolytically
formed, hydrated oxide gel is deposited on the metal surface. Treatment is restricted to
nonelectrolytic methods, and materials used must be qualified to MIL-C-81706
(Chemical Conversion Materials for Coating Aluminum and Aluminum Alloys, issued
November 13, 1979). A very important requirement in MIL-C-5541 is the corrosion
resistance requirement of 168 hours of salt spray exposure. In addition, paint adhesion
requirements and tests are given. Two classes of coatings are specified; one for
maximum corrosion protection (Class 1A) and one where some electrical conductivity is
required, i.e., for static discharge (Class 3).
HMSC has placed a high priority on replacing the chrome conversion coating process
with a more environmentally benign process. Currently, the chrome conversion coating
process lines are the largest, single source of hexavalent chromium emissions at both the
Tucson, Arizona, and the El Segundo, California, operations of HMSC. Hexavalent
chromium in significant percentages is found in both the deoxidizer and the chrome
conversion baths of the process. Because hexavalent chromium is emitted from these
baths, special health monitoring of process technicians must be performed regularly. In
addition, yearly computerized plume modeling is required by local air and water quality
regulations. Special handling and treatment of spent chrome baths is also required.
Besides the environmental, health, and safety disadvantages of the present chrome
conversion coating process, there are some process-related drawbacks. Exposure to
elevated temperatures reduces corrosion resistance of the hydrated amorphous gel coating
formed by this process. Unpainted chrome conversion coatings will begin losing
corrosion resistance properties if exposed to temperatures of 140oF (60oC) or above. This
restricts subsequent drying processes especially for partially painted parts. Another
process restriction is the time between the conversion coat treatment and the painting
processes. Paint adhesion declines significantly if surfaces are not painted within
72 hours after the chrome conversion coating is applied.
2.1. Baseline Process Flow
The sequence of steps for the HMSC Iridite 14 chrome conversion coating process
is shown in Figure 1.
Potential Alternatives Report 3
Load
Parts
Chrome Counterflow
Counterflow
Alkaline
Deoxidizer Rinse
Rinse
Clean
Step 1 Step 3 Step 4
Step 2
Unload
Coated
Hot
Chromate Clean Hot Parts
Air
Conversion Water Water
Dry
Coat Rinse Rinse
Step 8
Step 7
Step 6
Step 5
Figure 1. Flow of Baseline Chrome Conversion Coating Process
2.2. Baseline Process Description
All parts are initially degreased off-line in an automated Ransohoff Aqueous
Cleaning System using W.R. Grace Daraclean 282. After precleaning, the parts
are loaded onto the hoist. This process is automated and the coating of 2024,
6061, 7075, and 356 castings makes up the bulk of all work. Deionized water is
used to make up the rinses and the process baths. Table 2 shows the specific
operating parameters for each step of the process.
4 Potential Alternatives Report
Table 2. Steps of Baseline Chrome Conversion Coating Process
Step Description Dwell Time Temperature
No. (min)
1 Alkaline Clean 10-12 150癋
2 Counterflow Rinse 0.5-1 Room Temp
3 Chrome Deoxidizer 8-10 Room Temp
4 Counterflow Rinse 0.5-1 Room Temp
5 Chrome Conversion Coat 0.75 Room Temp
6 Clean Water Rinse 0.5-1 Room Temp
7 Hot Water Rinse 0.5-1 130癋
8 Hot Air Dryer As Required 130癋
The following describes each step of the current chrome conversion coating
process.
1. Alkaline Clean: This is performed to remove all traces of organic
contamination. Alkaline nonetch and etch (for special sequences)
cleaners are used. For heat-treatable alloys to be cleaned by
alkaline etching, an acid deoxidizer predip is used from 15 seconds
to 2 minutes to ensure a uniform etch. Cleaner temperature and
transfer time from cleaner to rinse is closely monitored to avoid
drying the cleaner on the work surface before rinsing. The
currently used cleaner is Parker Amchem's Ridoline 322.
2. Counterflow Rinse: Thorough rinsing after each processing step is
essential. Clean, fresh water immersion rinses are used. A
counterflow rinse process is used to control drag-out and
evaporation, which can affect rinse water quality. After the
cleaning and rinsing, the part should have a water break-free
surface.
3. Chrome Deoxidizer: This removes metal oxides, leaving the
surface chemically clean and receptive to chemical coating. When
a nonetch alkaline cleaner is used, a chromic acid deoxidizer step
is used for all heat-treated alloys, but is optional for nonheat-
treated alloys and die castings. If the deoxidizer step is omitted,
rinsing must be particularly thorough. When an alkali etch cleaner
is used, a chromic acid deoxidizer for desmutting follows. For
desmutting of alloys containing more than 1% silicon, a nitric-
hydrofluoric acid mix is used.
4. Counterflow Rinse: This is the same as step 2, but uses separate
tanks. Thorough rinsing before the chrome treatment step is
essential.
5. Chrome Treatment: Alodine 1200 and Alodine 1500 are used for
chrome treatment. The chrome bath is made up with deionized
water. The concentration of active ingredients (primarily
Potential Alternatives Report 5
hexavalent chromium) in the bath is maintained within ?0% of
the initial value. The acidity (as measured by pH) of the bath must
be maintained to produce uniform results. The final criterion for
satisfactory bath performance is the property of the coating itself,
particularly color, satisfactory adherence to the metal surface,
freedom from powderiness, and performance, as indicated by a salt
spray test.
6. Clean Water Rinse: This is the same as step 2.
7. Hot Water Rinse: The final rinse is hot, deionized water at a
maximum temperature of 54癈 (130癋). An adequate flow of
water is maintained to prevent concentration of impurities by
evaporation.
8. Hot Air Dryer: A conventional drying oven is used, and the
chrome surface does not attain a temperature greater than 54癈
(130癋) in the drying process.
2.3. Baseline Process Equipment
The current equipment is an automated, dual-hoist, U-shaped tank line. This
multiple process line has 43 stations, each having a 450-gallon tank. Most of the
tanks are made of 316 stainless steel. Some stations, like the alkaline cleaner and
deoxidizer tanks, are dual stations with a capacity of 900 gallons per tank. There
are three stations available for full-scale testing of non-chrome alternative
processes. Two of these stations can be heated.
2.4. Baseline Material and Energy Usage
More than 24,000,000 square inches of parts are coated at this HMSC site in a
typical year. The total material costs for the continuous chrome conversion
coating process are approximately $18,000 per year. These costs include all the
chemicals and other materials, except parts, needed to operate the process on a
continuous basis. The total utilities and facility costs are approximately $88,000
per year. These costs include all electrical and closed-loop wastewater treatment
costs.
2.5. Baseline Waste and Emissions Summary
This HMSC site has an ion exchange unit on the rinse water tanks to remove
much of the chromium from the rinse water. After passing through the ion
exchange unit, wastewater from the conversion coating line goes to a central water
treatment facility for all HMSC facilities, and is then reutilized in a closed-loop
system. Spent dip tank solutions are checked weekly and maintained at optimal
performance. When solutions become contaminated to a degree that they cannot
6 Potential Alternatives Report
acceptably perform, the tank is dumped and refreshed. The dumped bath is
disposed of as hazardous waste.
2.6. Environmental, Safety, and Occupational Health (ESOH) Status for the
Baseline Process
Although chrome conversion coating offers many advantages, its use of
hexavalent chromium is strictly regulated due to the compound's toxicity and
suspected carcinogenicity. For example, regulations pursuant to the Clean Air Act
(CAA), Clean Water Act (CWA), and the Resource Conservation and Recovery
Act (RCRA) contain provisions regulating waste streams from metallic finishing
operations that contain hexavalent chromium. The U.S. Environmental Protection
Agency (EPA) also lists chromium as one of the 17 materials that are targeted for
strict regulation. In addition, worker exposure to hexavalent chromium in the
work place is regulated by the Occupational Safety and Health Administration
(OSHA) because it can be harmful to workers who maintain and operate the
treatment and rinse baths. Continued use of the chrome process carries a growing
risk of workplace and environmental liability, along with increased costs for
trucking inventories, monitoring emissions, and reporting usage of chromium
compounds and resulting wastes. These regulatory driving forces are increasing
manufacturing costs and hazardous material liability, leading industry to identify,
evaluate, and implement acceptable alternatives for the chrome conversion
coating.
2.6.1. Environmental Issues
The baseline chrome conversion coating process as described above
contains many chemicals regulated, restricted, or otherwise listed by the
U.S. EPA. The use of these chemicals requires environmental reporting,
permits, fees, and/or other initiatives. The constituents of Ridoline 322,
Isoprep 188, and Iridite 14, are the main sources of these chemicals that
require EPA compliance.
Due to their toxicity, potassium dichromate (Isoprep 188) and chromic
acid (Iridite 14) are listed as characteristic hazardous wastes (D007) under
RCRA. The use of Daraclean 282 and Ridoline 322 does not appear to
generate any RCRA hazardous wastes.
The CAA lists both potassium dichromate (Isoprep 188) and chromic acid
(Iridite 14) as hazardous air pollutants (HAPs) under the general category
of chromium compounds. Ridoline 322 contains 2-butoxyethanol, which
is also listed as a HAP. While certain glycol ethers are regulated as HAPs
under Section 112(b) of the CAA, the particular structure of the glycol
ethers found in Daraclean 282 does not appear to be regulated. Classifying
Potential Alternatives Report 7
a stationary source as a "major" source depends upon the amount of HAPs
emitted from that source.
The CWA lists 2-butoxyethanol as a pretreatment pollutant, trisodium
phosphate as a hazardous substance, and potassium dichromate and
chromic acid as toxic pollutants, priority pollutants, and hazardous
substances. If discharged to a publicly owned treatment works (POTW),
pretreatment pollutants, toxic pollutants, and priority pollutants must
undergo pretreatment to ensure that their discharge is compatible with the
capabilities of the POTW. In addition, toxic and priority pollutants must
be treated before they can be directly discharged to receiving waters.
Spills or other discharges of hazardous substances into navigable waters
must be reported when the amount spilled exceeds the substance's
reportable quantity. The use of Daraclean 282 does not appear to generate
any regulated wastewaters.
EPA includes chromium compounds on the "33/50 Program" list of 17
high-priority chemicals targeted for strict regulation. Both Isoprep 188
and Iridite 14 are sources of chromium.
Section 313 of the Emergency Planning and Community Right-to-Know
Act (EPCRA) lists glycol ethers (Daraclean 282), 2-butoxyethanol
(Ridoline 322), potassium dichromate (Isoprep 188), and chromic acid
(Iridite 14) as reportable on Toxic Release Inventory (TRI) reports.
The Comprehensive Environmental Response, Compensation, and
Liability Act (CERCLA) lists 2-butoxyethanol, trisodium phosphate
(Ridoline 322), potassium dichromate (Isoprep 188), and chromic acid
(Iridite 14) as hazardous substances. Spills or other releases of these
substances must be reported when the amount spilled exceeds the
substance's reportable quantity.
2.6.2. Health and Safety Issues
OSHA has set Permissible Exposure Limits (PELs), and the American
Conference on Governmental Industrial Hygienists (ACGIH) has set
Threshold Limit Values (TLVs), for chemical hazards in the workplace.
Table 3 lists those chemicals used in the baseline conversion coating
process and their worker exposure limits.
8 Potential Alternatives Report
Table 3. Chemicals in Baseline Conversion Coating Process and Worker
Exposure Limits
Chemical OSHA PEL ACGIH TLV
5 mg/m3
Borax None
2-Butoxyethanol 50 ppm (Skin) 25 ppm (Skin)
(Ethylene Glycol
Monobutyl Ether)
Ethanolamine 3 ppm 3 ppm (TWA)
6 ppm (STEL)
15 mg/m3 Total 10 mg/m3 Total
Calcium Silicate
5 mg/m3 Respirable
0.05 mg/m3 as Cr(VI)
Potassium Dichromate 0.1 ppm as CrO3 (Ceiling)
2.5 mg/m3 as F 2.5 mg/m3 as F
Potassium
Fluoroborate
0.05 mg/m3 as Cr(VI)
Chromic Acid 0.1 ppm as CrO3 (Ceiling)
TWA = Time-Weighted Average concentration for a normal eight-hour workday
STEL = Short-Term Exposure Limit, defined as a 15-minute TWA exposure which
should not be exceeded at any time during a workday
The chemicals used in the baseline conversion coating process were also
examined for their potential adverse effects on human health.
? The glycol ethers used in Daraclean 282 are human
neurotoxins and experimental animal teratogens, but not
carcinogenic or genotoxic.
? Ridoline 322 contains no known or suspected human
carcinogens or teratogens. However, borax, 2-
butoxyethanol, and ethanolamine are reproductive toxicants
in laboratory animals.
? Ethanolamine is a known human genotoxin, and mutation
data has been reported for borax and trisodium phosphate.
? 2-Butoxyethanol and ethanolamine are known human
neurotoxins.
? Isoprep 188 contains no known or suspected human
neurotoxins or teratogens. However, potassium dichromate
is an experimental animal teratogen and a known human
carcinogen and genotoxin.
? Mutation data has been reported for sodium bisulfate.
? Iridite 14 contains no known or suspected human
neurotoxins or teratogens. However, chromic acid is an
experimental animal teratogen and a known human
carcinogen and genotoxin.
Potential Alternatives Report 9
Ventilation is required to maintain airborne contaminants below the PELs
and TLVs. In addition, personal protective equipment is required, such as
eye goggles or face shields, neoprene or polyvinyl gloves, appropriate
protective clothing, and a dust filter mask or respirator.
2.7. Baseline Capital and Operating Costs
A cost-benefit analysis (CBA) methodology was developed and used to capture
costs of the current chrome conversion coating process. The CBA established the
baseline for those operations affected by the possible non-chrome conversion
coating alternatives.
A new Environmental Life-Cycle Cost Analysis Tool (ELCCAT) developed by
Hughes Environmental Systems, Inc. was used to conduct this evaluation. The
process line for the HMSC chrome conversion coating was used to provide actual
data on typical production costs. Extensive data was collected on the current process,
including operating and environmental costs. Information was collected on every part
processed through the chrome conversion coating line at the Tucson facility covering
the two-year period from January 1994 to December 1995. Process times, labor,
material, and equipment costs, and costs pertaining to hazardous waste generation
were obtained.
Table 4 provides life-cycle costs for the current chrome process. This table
illustrates the various cost categories considered by the ELCCAT model in
developing the actual as well as collected costs. Projected values were determined
by first establishing costs on a per unit area of part basis. Annual costs were then
determined by multiplying the per unit area costs for each factor considered by the
total surface area of all parts processed during a typical year. The results indicate
that the current chrome process costs approximately $420,000 on an annual basis.
The costs provided here are unique to the HMSC manufacturing operation.
Environmental regulations in some areas will differ. Also, the extensive
wastewater reclamation and recycling capability of the HMSC operations may not
be necessary elsewhere. Factors such as these would tend to result in a different
life-cycle cost for other sites.
10 Potential Alternatives Report
Table 4. Annual Costs for Baseline Chrome Conversion Coating
Category Cost (dollars/year)
Equipment 110,000
Utilities/ Facilities 88,000
Material 18,000
Labor 94,000
Hazardous Waste 27,000
Wastewater 86,000
TOTAL 420,000
The cost impact of the use of chrome conversion coating on the DoD Sustainment
Community is difficult to estimate without conducting a thorough analysis. Due
to chrome's strength in resisting corrosion, very little depot repair is required.
System inspections can take place every six, eight, or ten years depending on
system requirements. Touch-up and repair is simple using a brush-on method of
applying the conversion coating. The use of a self-contained "high-lighter"
containing chrome conversion coating for touch-up areas has dramatically reduced
waste and possible worker exposure to chemicals doing maintenance and repair.
Therefore, from the strict viewpoint of labor and operating costs, chrome
conversion coating can be an inexpensive way of providing lasting corrosion
resistance for parts not directly exposed to the environment. It also represents a
way for improving paint adhesion on parts that will be exposed. However, if the
life-cycle costs and future liability of chrome conversion coating on the
Sustainment Community were evaluated, it is anticipated that the process would
reveal itself to be expensive.
Potential Alternatives Report 11
3. IDENTIFIED ALTERNATIVES AND PRELIMINARY SCREENING
To identify alternatives to chrome conversion coatings, Concurrent Technologies
Corporation (CTC) was tasked to perform a technology survey. Alternatives were desired
that could pass one or more of the corrosion resistance or contact-electrical resistance
performance requirements of MIL-C-5541 or MIL-C-81706 for Class 1A or Class 3
coatings. Nine commercially available or near-commercially available alternative
technologies were identified through a technology survey. The results of this survey are
detailed in Appendix A and summarized in Section 3.1.
Vendors of these alternative technologies were identified, and vendor product information
was obtained for 20 available products in November 1995. Vendor product information
is provided in Appendix B and summarized in Section 3.2. Further screening of these
products was conducted to refine the list to those that appeared most viable, as listed in
Table 5 below. A discussion of the screening process is presented in Section 3.3.
Table 5. Most Viable Alternatives to Chrome Conversion Coating
Product Technology Company
Alodine 2000 Cobalt-Based Coating Parker Amchem
Alumicoat 6788 Proprietary Elf Atochem
Technique
Chrome-Free Proprietary Hughes Aircraft Company
Conversion Coating Technique
(CFCC)
Sanchem FP (Full Manganese Oxide Sanchem
Process) Film
These viable alternative products were selected by DoD and OEM technical
representatives to undergo further evaluation (refer to Sections 4 and 5). The following
sections explain how these products were selected.
3.1. Alternative Technology Selection
Nine commercially or near-commercially available alternative technologies were
identified in the technology survey, as summarized in Table 6. The selection of
these technologies was based on an evaluation of historical test results, and
experience from DoD and OEM technical representatives. Additional information
regard these technologies is provided in Appendix A.
12 Potential Alternatives Report
Table 6. Identified Alternative Technologies to Chrome
Conversion Coating
Alternative Technology Reference Section in Appendix A
Sol-Gel Coatings A.2.1
Fluorozirconium Coatings A.2.2
Cobalt-Based Coatings A.2.3
Rare Earth Metal Salts A.2.4
Manganese Oxide Films A.2.5
Fluotitanic Coatings A.2.6
Talc Coatings A.2.7
Anodizing A.2.8
Proprietary Techniques A.2.9
A brief description of each alternative technology is provided below.
Sol-Gel technology uses polymers or metal oxides either alone or mixed to form
complexes by the hydrolysis of appropriate precursor compounds. Sol-Gels can
form powders or thin films that inhibit corrosion on substrates.
Fluorozirconium coating technology uses complexed transition metal salts to
create a thin film on a substrate material similar to a conversion coating.
Specifically, zirconium is mixed with fluorine to create fluorozirconium, which
reacts with the part surface to form a coating.
Cobalt-based coatings use cobalt and molybdenum to treat substrate materials.
The coatings created are low in electrical resistance and are good for corrosion
resistance.
Rare Earth Metal (REM) salts may be applied by heated immersion to create
protective layers on substrate materials. REMs provide corrosion resistance by
producing a protective oxide film.
Potassium permanganate solutions can be used to create manganese oxide films
on substrates. Manganese oxide films resulting from potassium permanganate
treatment closely match the corrosion resistance of traditional chromic oxide films
used in conversion coatings. Potassium permanganate coatings are very effective
in protecting aluminum alloys.
Fluotitanic coatings, deposited from acid solutions with organic polymers, require
few process steps, and can usually be done at ambient temperatures. Although
these coatings have been widely used in a variety of applications, they have not
been used in the aerospace industry.
Potential Alternatives Report 13
Talc coatings, which are typically applied to aluminum substrates, are resistant to
corrosion. These polycrystalline coatings are applied by precipitating aluminum-
lithium compounds and other anions in an alkaline salt solution.
Anodizing is a process in which a metal surface is converted to an oxide layer,
producing a tough, adherent surface layer. A thick oxide layer can be produced by
immersing a part in an electrolytic solution and passing an electrical current
through it, similar to electroplating. Then, by placing the part in boiling water, the
film's pores can be sealed. As a result, the oxide changes from one form to
another.
Proprietary techniques to replace chrome conversion coatings are available
commercially, or are in a final development stage. Since these techniques are kept
secret, little is known about the chemical or physical changes that occur in the
processing. Historical data shows that these techniques have significant value.
Because they are available for general use as possible alternatives to chrome
conversion coatings, they were identified as alternatives.
3.2. Product Identification
After the nine alternative technologies were selected, commercially or near-
commercially available alternative products associated with the technology
categories were identified as part of the technology survey. Twenty alternative
products to chrome conversion coatings were identified in November 1995, as
shown in Table 7 below. Information collected and evaluated during the survey
indicated that these alternative coatings and processes commonly generate less
pollution than chrome conversion coating, and have less health and safety risks
associated with them.
Table 7. Identified Alternative Products to Chrome Conversion Coatings
Product Manufacturer/Distributor Technology
1 Aeroglaze Lord Corporation Sol-Gel Coatings
2 Alcoat 1470 Circle-Prosco, Inc. Fluorozirconium
3 Alcoat 3000 Circle-Prosco, Inc. Coatings
4 Alcoat 4000 Circle-Prosco, Inc.
5 Alcoat 5000 Circle-Prosco+669, Inc.
6 Alodine 2000 Parker Amchem Cobalt-Based Coatings
7 Ce-Mo 6061 University of Southern Rare Earth Metal Salts
California
8 Patclin 1910B Patclin Chemical Company, Manganese Oxide
Inc. Films
(Table 7 continued on next page)
14 Potential Alternatives Report
Table 7. Identified Alternatives Products to Chrome Conversion Coatings
(Continued)
Product Name Manufacturer/Distributor Technology
9 Sanchem FP (Full Sanchem Manganese Oxide
Process) Films
10 Permatreat 611 Betz Laboratories Fluotitanic Coatings
11 Sandia 1 Sandia National Talc Coatings
Laboratories
12 Sandia 2 Sandia National
Laboratories
Sulfuric-Boric Acid Boeing Aerospace Anodizing
13
Anodizing Corporation
14 Alumitec Alumitec Products
Corporation
Alumicoat 6788 Elf Atochem -- Turco Proprietary Techniques
15
Products Division
16 Chemcote L497260A Brent America, Inc.
Chrome-Free Hughes Aircraft Company
17
Conversion Coating
(CFCC)
E-CLPS 923 Bulk Chemicals, Inc.
18
E-CLPS 923X Bulk Chemicals, Inc.
19
Turco 2438-28D Elf Atochem -- Turco
20
Products Division
To provide a basis for determining which of these products may be most viable,
technical, environmental, health, safety, and market information was collected on
each of the alternatives during the technology survey. This information is
summarized in Table 8, and briefly discussed below. (A more detailed description
of each product, including historical test results and associated environmental,
health, and safety concerns for each identified product, is presented in
Appendix B.).
3.2.1 Technical Criteria
In MIL-C-5541 and MIL-C-81706, two classes of coatings are discussed.
Class 1A coatings are for maximum corrosion resistance with or without
paint. Class 3 coatings are for corrosion resistance that has a contact
electrical resistance requirement. For Class 1A coatings, there are two
significant differences between MIL-C-5541 and MIL-C-81706. For
corrosion resistance, MIL-C-5541 requires a 168-hour salt spray test, and
MIL-C-81706 requires a 336-hour salt spray test. For paint adhesion,
MIL-C-81706 requires both the wet tape test and the knife test while
MIL-C-5541 only requires the wet tape test. Class 3 coatings in both
Potential Alternatives Report 15
specifications require the contact electrical resistance test and a 168-hour
salt spray test for corrosion resistance.
In Table 8, an indication is provided whether an alternative passed or
failed a particular military specification to which it was tested. An
alternative is listed as "passed" if the required alternative passed all the
performance requirements in the listed military specification and coating
class. Special notes are given for alternatives that were not tested
according to the specification.
3.2.2. Environmental Criteria
The results of the environmental review performed by the technical
representatives are shown in Table 8. A product is noted as having
"passed" environmental regulatory criteria if it contained no constituents
that are banned, or scheduled to be banned, by the EPA. No alternatives
identified in this report contained banned substances; therefore, all
products passed this screening criterion.
3.2.3. Health and Safety Criteria
Material safety data sheets (MSDSs) were reviewed to determine whether
any constituent or agent (part of an alternative product) has been identified
in Sax's Dangerous Properties of Industrial Materials as a known or
suspected human carcinogen, genotoxin, teratogen, or neurotoxin. A
product was deemed to have "failed" health and safety criteria if it
exhibited any of these health hazards. As shown in Table 8, 10 of the 20
alternatives passed the health and safety criteria. Although a constituent
(and the corresponding product) may be considered "toxic" by the above
criteria, the hazard it presents (a function of toxicity and exposure) can be
mitigated through exposure controls.
3.2.4. Commercial Availability
Sixteen of the identified products are commercially available, as indicated
in Table 8.
16 Potential Alternatives Report
Table 8. Key Characteristics of the Identified Chrome Conversion Coating Alternatives
Technical Criteria
Class 1A Class 1A Health
Requirement Requirement Class 3 Environment and Commercially
Availableb
Product MIL-C-5541 MIL-C-81706 Requirement al Criteria Safety
Criteriaa
Passedc
Aeroglaze Sol-Gel Failed Failed Passed Failed Yes
Alcoat 1470 Failed Failed Failed Passed Passed Yes
Alcoat 3000 Failed Failed Failed Passed Passed Yes
Alcoat 4000 Failed Failed Failed Passed Passed Yes
Passedc
Alcoat 5000 Failed Failed Passed Passed Yes
Passedc
Alodine 2000 Passed Passed Passed Failed Yes
Alumicoat 6788 Passed Failed Failed Passed Failed Yes
Passedd Passedd
Alumitec Failed Passed Failed Yes
Ce-Mo 6061 Failed Failed Failed Passed Failed Yes
Passedc
Chemcote L497260A Failed Failed Passed Failed Yes
Failede
CFCC Passed Passed Passed Passed No
E-CLPS 923 Failed Failed Failed Passed Passed Yes
E-CLPS 923X Failed Failed Failed Passed Passed Yes
Patclin 1910B Failed Failed Failed Passed Passed Yes
Permatreat 611 Failed Failed Failed Passed Passed Yes
Sanchem FP Failed Failed Failed Passed Passed Yes
Sandia 1 Failed Failed Failed Passed Failed No
Sandia 2 Failed Failed Failed Passed Failed No
SBAA Passed Passed Failed Passed Failed Yes
Passedc Passede
Turco 2438-28D Failed Failed Passed No
a
A "Failed" in this category means the product contains constituents determined to be known or suspected toxins based on available literature.
b
As of November 1995
c
The coating passed pre-salt spray contact electrical resistance tests; however, the military specification was not followed for post-salt spray tests.
d
Passed salt spray tests only. No wet tape test was performed.
e
Compound is not commercially available and compound constituents are proprietary property.
Potential Alternatives Report 17
3.3. Preliminary Technical Screening of Identified Alternatives
The technical representatives for the HMSC JG-APP site determined that it would
not be feasible to conduct complete JTP testing and analysis for all 20 identified
alternatives. Therefore, the alternatives underwent a multiple-step, initial
screening process by the technical representatives to reduce the number of
alternatives to be tested. The information used as a basis for this preliminary
screening is presented in Table 9, and is discussed in this section.
The Joint Test Protocol for the Validation of Alternatives to Chrome Conversion
Coatings for Aluminum Alloys 2024, 6061, 7075, and Ion Vapor Deposited
Aluminum on Steel (JTP), dated May 21, 1996, contains the requirements for three
groups of chemical conversion coatings. Each group corresponds to one of the
three general uses of chemical conversion coatings. The three groups are:
? Group 1: Unpainted surfaces requiring maximum corrosion
resistance
? Group 2: Painted surfaces requiring maximum primer-to-substrate
adhesion
? Group 3: Unpainted surfaces requiring lower electrical resistance.
According to the JTP, Group 1 coatings must pass the corrosion resistance test
(336-hour salt spray); Group 2 must pass the paint adhesion test (wet tape value of
5); and Group 3 must pass the contact electrical resistance test (less than
5 milliohms/in2 resistance as applied). The results obtained for these three critical
tests were reviewed in detail and used to prescreen the identified alternatives. A
summary of this existing data is presented in Table 9.
The DoD and HMSC technical representatives agreed that the primary objective
was to identify and validate a chrome-free conversion coating that could be used
on all affected production programs; one alternative would need to work on all
substrates and meet all performance requirements. Therefore, alternatives shown
by historical tests results to have passed all three tests were most desirable. As
shown in Table 9, few alternatives previously passed the 336-hour test for salt
spray corrosion resistance, and in most cases passed for just one alloy. None of
the identified processes met the performance criteria for all alloys and all tests.
(Ion vapor deposition of aluminum on steel had not been previously tested as a
substrate with these alternative coatings.)
18 Potential Alternatives Report
Using the historical test data, the technical representatives selected the top seven
most-promising alternative processes for further consideration. These alternatives
were:
1. Alcoat 4000 4. Allumitec 7. SBAA.
2. Alodine 2000 5. Chemcote L497260A
3. Alumicoat 6788 6. CFCC
A summary of the test results for the seven alternatives is shown in Table 10,
along with results for the baseline conversion coating process (Alodine 600), for
comparison. Although none of the selected alternatives met all the JTP criteria,
neither did the baseline process. Therefore, for the purposes of prescreening, the
requirement of passing all three tests on all three substrates was dropped.
After selecting the seven alternatives, a further evaluation of these alternatives
was conducted by the technical representatives, which involved a closer
examination of the prior performance data and the relative ease of process
implementation (i.e., "drop in" replacement). As a result of this analysis, four
alternatives (Alcoat 4000, Alumitec, Chemcote L497260A, and SBAA) were
dropped from further consideration, and one product, Sanchem FP, was added to
the list of alternatives. The following subsections of this PAR discuss this further
evaluation of the seven screened alternatives, plus the Sanchem FP product.
19
Potential Alternatives Report
Table 9. Chrome Conversion Coating Alternatives ?Existing Performance Data
JTP Criteria
336 5
5
Product Aluminum Alloy
2024 6061 7075 2024 6061 7075 2024 6061 7075
0.23b
Aeroglaze Sol-Gel 24 168 24 0 0 0 41.5 3.49
Alcoat 1470 48 168 24 0 0 0 597 9.93 909
Alcoat 3000 24 168 24 4 5 5 901 8.00 238000
Alcoat 4000 24 336 24 4 3 3 1820 3800 266
1.88b
Alcoat 5000 24 24 24 3 3 3 807 296
2.08b
Alodine 2000 168 336 240 5 3 3 764 1740
Alumicoat 6788 240 1008 1008 5 5 5 3130 2640 737
Alumitec >816 N.T. N.T. N.T. N.T. N.T. N.T. 174 N.T.
Ce-Mo 6061 24 24 24 3 5 5 1400 1.60 66.0
0.43b
Chemcote L497260A 24 504 24 5 4 5 9.45 4.70
336
CFCC 264 432 5 5 5 N/T 57 N/T
E-CLPS 923 24 24 24 4 5 3 3.55 0.77 29.6
E-CLPS 923X 24 24 24 5 3 5 6.10 0.40 7.9
Patclin 1910B 24 24 24 4 1 4 13.1 1.68 38.0
Permatreat 611 24 24 24 5 5 5 37.2 0.54 253
Sanchem FP 24 24 24 4 5 5 24.4 1.31 55.0
Sandia 1 24 24 24 3 4 3 3.84 0.48 3.98
Sandia 2 24 168 24 3 3 3 2370 7.16 529000
SBAA >336 N.T. >336 5 N.T. 5 N.T. >5 N.T.
1.53b
Turco 2438-28D 96 240 48 0 0 0 22900 839
a
Reference MIL-C-5541 and MIL-C-81706
b
The coating passed pre-salt spray contact electrical resistance tests; however, standard procedures were not followed for post-salt spray tests.
N.T. =Not Tested
21
Potential Alternatives Report
Table 10. Screened List of Alternative Products
Corrosion Resistance Paint Adhesion Contact Elec. Resistance
(milliohms/in2)
(Hours of Salt Spray) (Scale 1-5)
JTP Criteria
336 5
5
Product
Aluminum Alloy
Baseline 2024 6061 7075 2024 6061 7075 2024 6061 7075
Alodine 600 336 1008 1008 4 5 4 2.07 0.61 19.7
Alternative
1 Alcoat 4000 24 336 24 4 3 3 1820 3800 266
2 Alodine 2000 168 336 240 5 3 3 764 2.08 1740
3 Alumicoat 6788 240 1008 1008 5 5 5 3130 2640 737
4 Alumitec >816 N.T. N.T. N.T. N.T. N.T. N.T. 174 N.T.
5 Chemcote 24 504 24 5 4 5 9.45 0.43 4.70
L497260A
336
6 CFCC 264 432 5 5 5 N.T. 57 N.T.
7 SBAA >336 N/T >336 5 N.T. 5 N.T. N.T. N.T.
N.T. = Not Tested
22 Potential Alternatives Report
3.3.1. Alcoat 4000
Alcoat 4000 by Circle-Prosco Inc. is a simple "drop-in" replacement.
This alternative is being used at Chrysler to coat heat exchangers.
Though this alternative met the 336-hour requirement for 6061
aluminum, it failed corrosion resistance on the other alloys. Neither
paint adhesion nor contact electrical resistance test results were
favorable. Because this alternative has shown poor performance in the
past, it is not being considered for further review. Table 11 shows the
historical test results for Alcoat 4000.
Table 11. Historical Test Results for Alcoat 4000
Test Salt Spray Wet Tape Contact Elec. Resistance
(milliohms/in2)
(hours) Adhesion
336 5
Passing Value 5
Alloy 2024 24 4 1,820
Alloy 6061 336 3 3,800
Alloy 7075 24 3 266
3.3.2. Alodine 2000
Alodine 2000 by Parker Amchem uses chromic acid in the etching step.
However, materials other than chromic acid can be used to etch
aluminum. One example is Deoxalum 2200 by Parker Amchem, in
which nitric acid is the main component. By using Deoxalum 2200 to
etch, chrome is eliminated. Thus, the inclusion of Deoxalum 2200
makes the Alodine 2000 process more environmentally friendly, while
still maintaining equivalent coating performance. For these reasons,
Alodine 2000 was retained for further consideration. Table 12 shows the
historical test results for Alodine 2000.
Table 12. Historical Test Results for Alodine 2000
Test Salt Spray Wet Tape Contact Elec. Resistance
(milliohms/in2)
(hours) Adhesion
336 5
Passing Value 5
Alloy 2024 168 5 764
Alloy 6061 336 3 2
Alloy 7075 240 3 1,740
3.3.3. Alumicoat 6788
23
Potential Alternatives Report
Elf Atochem's Alumicoat 6788 is considered a "drop-in" type
replacement coating. Alumicoat 6788 has very good paint adhesion
characteristics, and resists corrosion on 6061 and 7075 aluminum alloys
very well. However, performance on 2024 aluminum falls short and the
coating's contact electrical resistance characteristics are very poor for a
Group 3 coating. Despite its shortcomings, the DoD and HMSC
technical representatives recommended additional testing of
Alumicoat 6788 to verify historical results and to evaluate process
improvements by Elf Atochem. Table 13 shows the historical test
results for Alumicoat 6788.
Table 13. Historical Test Results for Alumicoat 6788
Test Salt Spray Wet Tape Contact Elec. Resistance
(milliohms/in2)
(hours) Adhesion
336 5
Passing Value 5
Alloy 2024 240 5 3,130
Alloy 6061 1,008 5 2,640
Alloy 7075 1,008 5 737
3.3.4. Alumitec
Alumitec is marketed by Alumitec Products Corporation. These
coatings are actually sealers to be used with anodizing. For example,
Sulfuric-Boric Acid Anodize could use these sealants (see Section 3.3.8
for SBAA). This alternative has not been tested as extensively as the
other screened alternatives. In addition, this type of coating cannot
independently meet requirements without the aid of anodizing.
Therefore, for these reasons it was deleted from the list of alternatives.
Table 14 shows the historical test results for Alumitec.
Table 14. Historical Test Results for Alumitec
Test Salt Spray Wet Tape Contact Elec. Resistance
(milliohms/in2)
(hours) Adhesion
336 5
Passing Value 5
Alloy 2024 816 N.T. N.T.
Alloy 6061 N.T. N.T. 174
Alloy 7075 N.T. N.T. N.T.
N.T. = Not Tested
3.3.5. Chemcote L497260A
24 Potential Alternatives Report
Brent America's Chemcote L497260A quickly failed salt spray tests for
2024 and 7075 alloys, and paint adhesion for 6061. It was also
considered undesirable because it requires the use of proprietary cleaners
and etchants in addition to the proprietary deoxidation and conversion
coating chemicals. For these reasons, Chemcote L487260A was not
retained for further consideration. Table 15 shows the historical test
results for Chemcote L497260A.
Table 15. Historical Test Results for Chemcote L497260A
Test Salt Spray Wet Tape Contact Elec. Resistance
(milliohms/in2)
(hours) Adhesion
336 5
Passing Value 5
Alloy 2024 24 5 9.45
Alloy 6061 504 4 0.43
Alloy 7075 24 5 4.7
3.3.6. Chrome-Free Conversion Coating (CFCC)
Hughes Aircraft Company has developed the Chrome-Free Conversion
Coating (CFCC). An agreement between Hughes and the federal
government for royalty-free usage of the proprietary process is being
considered.
Previous testing of the coating showed that CFCC passed the 336-hour
requirement on 2024 and 7075 aluminum alloys, but it only lasted
264 hours on 6061 aluminum. Presently, this alternative has marginal
corrosion resistance performance, and improvements are needed before
it can meet the 336-hour minimum requirements. Because progress was
being made by HMSC in optimizing the process, CFCC was
recommended for further testing. Table 16 shows the historical test
results for CFCC.
25
Potential Alternatives Report
Table 16. Historical Test Results for CFCC
Test Salt Spray Wet Tape Contact Elec. Resistance
(milliohms/in2)
(hours) Adhesion
336 5
Passing Value 5
168
Alloy 1100 5 N.T.
336
Alloy 2024 5 N.T.
Alloy 6061 264 5 57
Alloy 7075 432 5 N.T.
N.T. = Not Tested
3.3.7. Sanchem FP (Full Process)
Although the findings of the technology survey indicated relatively poor
performance of Sanchem FP, Air Force engineers indicated that they
have had significant success with this alternative. As a result of these
technical discussions, Sanchem FP was added to the list of alternatives
for further consideration. Table 17 shows the historical test results for
Sanchem FP.
Table 17. Historical Test Results for Sanchem FP
Test Salt Spray Wet Tape Contact Elec. Resistance
(milliohms/in2)
(hours) Adhesion
336 5
Passing Value 5
Alloy 2024 24 4 24.4
Alloy 6061 24 5 1.31
Alloy 7075 24 5 55
3.3.8. Sulfuric-Boric Acid Anodizing (SBAA)
Sulfuric-Boric Acid Anodizing (SBAA), patented by the Boeing
Aerospace Corporation, provides good corrosion and paint adhesion.
However, the tough oxide layer has difficulty passing the contact
electrical resistance requirement. It is believed that with some minor
adjustments to dwell time, this requirement could be met. Because this
process is electrolytic, it is not considered a viable alternative to the non-
electrolytic chrome conversion coatings. Therefore, this alternative was
dropped from further consideration. Table 18 shows the historical test
results for SBAA.
26 Potential Alternatives Report
Table 18. Historical Test Results for SBAA
Test Salt Spray Wet Tape Contact Elec. Resistance
(milliohms/in2)
(hours) Adhesion
336 5
Passing Value 5
Alloy 2024 >336 5 N.T.
Alloy 6061 N.T. N.T. >5
Alloy 7075 >336 5 N.T.
N.T. = Not Tested
3.3.9. Summary
As a result of the more detailed technical review of the screened
alternatives, four alternatives Alodine 2000, Alumicoat 6788, CFCC,
and Sanchem FP were deemed viable alternatives, and were
recommended for further evaluation (see Table 19).
Table 19. Viable Alternatives to Chrome
Conversion Coating
Product Company
Alodine 2000 Parker Amchem
Alumicoat 6788 Elf Atochem
CFCC Hughes Aircraft Company
Sanchem FP Sanchem
Because of the limited scope of this screening, it is understood that this
assessment may not reveal every possible deficiency or hazard. CTC
assumes no responsibility for the safe operation and maintenance of the
manufacturing technology or for any environmental, safety, and
occupational health hazards or releases resulting from operation and
maintenance of the alternative manufacturing technology.
27
Potential Alternatives Report
4. PROCESS DESCRIPTIONS FOR VIABLE ALTERNATIVES
In further evaluating the alternatives to chrome conversion coating, it was necessary to
identify differences in the operating conditions of the alternative processes as compared
to the baseline process. For example, differences in the number of processing steps,
dwell times, and operating temperatures, as well as material and energy usage, are
important to document and consider. More detailed process information was generally
unavailable for the alternatives because such data varies from facility to facility.
However, as discussed below, fundamental information about each of the viable
alternatives was obtained for comparison.
All the viable alternatives use dip tanks, and therefore, would be expected to use
essentially the same type of processing equipment as the current coating process. The
number of steps is important because each step represents another dip tank in the
production line, which translates to higher capital equipment costs for implementation.
The number of steps is also an indicator of the processing time, especially because part
handling is frequently the major portion of the overall cycle time. Temperature is also
important because the lower the processing temperatures, the less material and energy
use during sustained operations (all things being equal). This translates into lower
operating costs. Finally, rework is an important part of any production line. Without a
developed method of touching up parts, the process could be impractical for field use.
The existence of a touch-up method is also an indicator of how well the process has
been developed. A summary of the key process parameters for each of the viable
alternatives is shown in Table 20.
Table 20. Process Parameters for Viable Alternatives
Baseline Alodine Alumicoat CFCC Sanchem
Process 2000 6788 FP
Number of Process Steps 12 9 7 11 12
Highest Processing 165 160 180 212 212
Temperature (oF)
Developed Touch-up Method Yes No Yes No Yes
As shown by Table 20, the alternative processes require no more steps, and in some
cases significantly fewer steps, than the current conversion coating process. In addition,
two of the four alternatives have established touch-up procedures in place. As a result,
it is anticipated that these benefits would help reduce the capital and operating cost of
the alternative processes.
Further process-related information for each of the four alternatives can be found in
Appendix B.
Use of nonchrome conversion coating is expected to lead to other benefits that cannot
easily be quantified for HMSC's process. Many of these items would also benefit the
28 Potential Alternatives Report
Sustainment Community. These items would include (in order of estimated impact on
cost):
1. Lower waste handling, storage, and disposal costs from the reduction or
elimination of process hazardous waste
2. Reduced need to develop environmental strategies
3. Reduced likelihood of having to re-engineer the process to meet new
environmental requirements
4. Lower wastewater treatment costs from the reduction or elimination of
toxic materials in the wastewater
5. Reduced cost to maintain environmental permits
6. Increased savings in developing and administering training programs.
Two operational disadvantages of the alternative processes are the operating
temperature and the material purchase cost. Three of the four viable alternatives exhibit
maximum processing temperatures greater than the baseline process temperature. This
has the potential to increase energy usage and therefore operating costs. In addition, all
the potential alternatives currently cost more per gallon than the present chrome
conversion coating, which would tend to increase operating costs. However, when
comparing these limitations to the number of potential advantages of the alternative
processes, it seems that the long-term benefits should easily outweigh the limitations.
29
Potential Alternatives Report
5. PRELIMINARY ESOH ANALYSIS OF VIABLE ALTERNATIVES
As part of the analysis of alternatives, each of the viable alternatives was qualitatively
assessed for associated ESOH concerns. This initial assessment was conducted to
determine whether there were any conspicuous ESOH issues that may need to be
addressed when selecting alternatives for testing. The results of this ESOH analysis are
contained in Appendix C and summarized below.
5.1. Environmental Issues
Each viable alternative was evaluated to determine the extent of their regulation
under the major federal environmental laws. Using available resources, each
alternative was evaluated based on the specified criteria:
? Air Emissions: Each alternative was analyzed to determine if it
is regulated under the CAA as a HAP, a VOC, or an ODS.
? Solid/Hazardous Waste Generation: Each alternative was
evaluated to determine whether its use generates solid waste, and,
if so, whether that waste may be regulated, as hazardous or
otherwise, under Subtitle C of RCRA.
? Regulated Wastewaters: Each viable alternative was analyzed to
determine whether its use would cause the discharge of any
wastewaters regulated under the CWA.
? Reporting Requirements: The viable alternatives were examined
to determine whether any of the constituents are required to be
listed on TRI reports under Section 313 of EPCRA.
? CERCLA Hazardous Substances: Each alternative was assessed
to determine if its constituents are listed as hazardous substances
under CERCLA.
? EPA 17: The constituents of each alternative were compared to
the "EPA 17" list. Those substances on the EPA 17 list have
been targeted by EPA because they are released in large
quantities each year; they are generally identified as toxic or
hazardous pollutants; and pollution prevention practices have the
potential to diminish releases of these chemicals. The EPA 17
are likely to be targeted for more stringent regulation.
5.2. Safety and Occupational Health Issues
Each viable alternative was given a toxicity ranking, exposure ranking, and an
overall hazard ranking based on the criteria set forth in Appendix C. Toxicity
was qualitatively reviewed, and each viable product was given a final toxicity
30 Potential Alternatives Report
ranking of high, medium, or low based on the analysis of available product
information. Parameters reviewed included median lethal concentration 50
(LC50) and/or median oral lethal dose 50 (LD50). The exposure criteria used in
the screening and ranking are OSHA PELs and the ACGIH TLVs. Three
exposure ranking levels and associated TLV and PEL intervals were chosen
based on the ACGIH recommendations. Exposure rankings of high, medium, or
low were assigned to candidate products. The hazard ranking is a combination
of the toxicity ranking and exposure ranking, and gives an overall ESOH
ranking to the viable alternative. A summary of the results of the ESOH
analysis can be found in Table 21.
As shown by the data in Table 21, all four alternative processes, in general, have
ESOH benefits over the current chrome conversion coating process. For
example, the hazard ranking is lower in all cases, the number of EPA 17 and
TRI reportable chemicals are fewer, and a fewer number of HAPs are emitted.
In the other ESOH categories, the alternatives either faired as well as, or better
than, the baseline process.
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Potential Alternatives Report
Table 21. Summary of ESOH Analysis for Viable Chrome Conversion Coating Alternatives
Air Wastes Generated
Emissions Waste- TRI CERCLA EPA 17
a a a
Product TR ER HR HAP VOC Solid Hazardous water Report HazSub List
Baseline Process
Alodine 600 H H H 3 U Yes Yes Yes 4 4 2
Alternative Products
1b 0c
Alodine M H M-H 0 Yes Yes No 2 1
2000
Alumicoat M M M 0 0 Likely No Yes 2 0 0
6788
CFCCd M M M 0 0 Yes Yes U 1 4 0
Sanchem FP M H M-H 1 U Yes U Yes 1 1 0
a
The toxicity ranking (TR), exposure ranking (ER), and hazard ranking (HR) are described in Appendix C.
b
If chromic acid is replaced with Deoxalum, only one HAP will be generated during the Alodine 2000 process; otherwise, 2 HAPs are emitted.
c
If chromic acid is replaced with Deoxalum, no EPA 17 chemicals will be generated during the Alodine 2000 process; otherwise one EPA 17 chemical is
present.
d
CFCC is a proprietary process; ESOH analysis is based on information on steps known at this time.
M =Medium
H = High
U = Unknown.
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Potential Alternatives Report
6. SELECTION OF POTENTIAL ALTERNATIVES
The process comparisons (Section 4) and the ESOH analysis (Section 5) were used as
final criteria for determining those products that should undergo testing in accordance
with the JTP. As discussed in Sections 4 and 5, the alternative processes generally are no
worse, and in most cases fair much better, than the current chrome conversion coating
process in terms of operational and ESOH issues, based on the available information.
From this analysis, the technical stakeholders determined that all the viable alternatives
should be carried through as candidates. As a result, the following is the list of potential
alternatives recommended for testing (see Table 22).
Table 22. Potential Alternatives to Baseline Chrome
Conversion Coating
Product Company
Alodine 2000 Parker Amchem
Alumicoat 6788 Elf Atochem
CFCC Hughes Aircraft Company
Sanchem FP Sanchem
34 Potential Alternatives Report
7. SUMMARY
At the HMSC JG-APP project site, chrome in chemical conversion coatings was
identified as a hazardous material of concern, and targeted for elimination or reduction.
Twenty alternatives to chrome conversion coatings were identified. Four of these
alternatives were considered viable alternatives based on historical test results. Technical
and ESOH aspects of these viable alternatives were analyzed. As a result of the analysis,
the technical stakeholders recommend that the following four potential alternatives be
tested according to the Joint Test Protocol for the Validation of Alternatives to Chrome
Conversion Coatings for Aluminum Alloys 2024, 6061, 7075, and Ion Vapor Deposited
Aluminum on Steel (HM-P-1-1), dated May 21, 1996.
? Alodine 2000 (Parker Amchem)
? Alumicoat 6788 (Elf Atochem)
? CFCC (Hughes Aircraft Company)
? Sanchem FP (Sanchem)
If nonchromate conversion coatings successfully pass the JTP testing and are
implemented, both HMSC and the Sustainment Community will be expected to receive a
number of benefits, many of which have a positive impact on operating costs. These cost
benefits might include:
1. Reduced labor and increased efficiency resulting from fewer processing
steps
2. Lower waste handling, storage, and disposal costs from the reduction or
elimination of process hazardous waste
3. Reduced need to develop environmental strategies
4. Reduced likelihood of having to re-engineer the process to meet new
environmental requirements
5. Lower wastewater treatment costs from the reduction or elimination of
toxic materials in the wastewater
6. Reduced cost to maintain environmental permits
7. Increased savings in developing and administering training programs.
35
Potential Alternatives Report
APPENDIX A
TECHNOLOGY SURVEY TO IDENTIFY
POTENTIAL ALTERNATIVES
TABLE OF CONTENTS
Page
A.1 INTRODUCTION.........................................................................................................A-1
A.2. DESCRIPTION OF SEARCH.....................................................................................A-2
A.3. IDENTIFIED ALTERNATIVES ................................................................................A-3
A.3.1. Technical Considerations .................................................................................... A-5
A.3.2. Environmental Issues .......................................................................................... A-6
A.3.3. Health and Safety Issues...................................................................................... A-6
A.3.4. Sol-Gel Coatings ................................................................................................. A-7
A.3.5. Fluorozirconium Coatings................................................................................... A-7
A.3.6. Cobalt-Based Coatings ........................................................................................ A-7
A.3.7. Rare Earth Metal Salts......................................................................................... A-7
A.3.8. Manganese Oxide Films...................................................................................... A-8
A.3.9. Fluotitanic Coatings ............................................................................................ A-8
A.3.10. Talc Coatings....................................................................................................... A-8
A.3.11. Anodizing............................................................................................................ A-8
A.3.12. Proprietary Techniques........................................................................................ A-9
A.4. BIBLIOGRAPHIC INFORMATION .......................................................................A-10
LIST OF TABLES
Search A ?DIALOG Database .......................................................................... A-2
Table A-1.
Search B ?DIALOG Database .......................................................................... A-3
Table A-2.
Table A-3. Search C ?NCMS Database ............................................................................... A-3
Table A-4. Identified Alternative Technologies to Chrome Conversion Coating................. A-5
Table A-5. Corrosion Resistance, Contact Electrical Resistance, and Paint Adhesion
Requirements of MIL-C-5541............................................................................. A-5
Table A-6. Corrosion Resistance, Contact Electrical Resistance, and Paint Adhesion
Requirements of MIL-C-81706........................................................................... A-6
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A.1 INTRODUCTION
HMSC follows military specifications for conversion coatings. The two main
specifications are MIL-C-5541 (Chemical Conversion Coatings on Aluminum and
Aluminum Alloys) and MIL-C-81706 (Chemical Conversion Coating Materials for
Coating Aluminum and Aluminum Alloys). These specifications describe chrome
conversion coatings that can be used for aluminum and aluminum alloys. These military
specifications categorize coatings as either Class 1A or Class 3. Class 1A coatings are for
maximum protection against corrosion. Surfaces that are treated with Class 1A coatings
may be painted or unpainted. Class 3 coatings are for applications that require corrosion
and electrical resistance.
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Potential Alternatives Report
A.2. DESCRIPTION OF SEARCH
Various information sources are available to CTC. Among the information sources used
to identify potential chrome conversion coating alternatives are database searches,
Internet searches, vendor contacts, the CTC Information Resource Centers, and personal
contacts. Three main searches were performed on databases. Two searches were on the
DIALOG database, which has access to 370 individual databases. The DIALOG
database contains over 260 million records, all of which are available with a variety of
search strategies. The DIALOG database search strategies used are named Search A and
Search B. The third search was performed on the National Center for Manufacturing
Sciences (NCMS) database. The NCMS search strategy is referred to as Search C.
Searches A, B, and C are described below in Tables A-1 through A-3.
Table A-1. Search A ?DIALOG Database
Search Sequence Search Term Number of Matches
A1 Chromate 22,889
A2 Conversion 464,267
A3 Chromate_conversion 665
A4 Alternat? 519,646
A5 Search A3 and Search A4 40
A6 Remove duplicates 23
Results Applicable Articles 13
A-2 Potential Alternatives Report
Table A-2. Search B ?DIALOG Database
Search Sequence Search Term Number of Matches
B1 Mil 8,862
B2 C 733,006
B3 5541 8
B4 Search B1_Search B2_Search B3 8
B5 81706 6
B6 Search B1_Search B2_Search B5 6
B7 Alternat? 200,193
B8 Replace? 80,025
B9 Traditional? 44,337
B10 (Search B4 or Search B6) and 5
(Search B7 or Search B8 or Search
B9)
B11 Remove Duplicates 1
Results Applicable Articles 1
Table A-3. Search C ?NCMS Database
Search Sequence Search Term Number of Matches
C1 Chromate_Conversion 18
Results Applicable Articles 12
In addition to the database searches, Internet sources were scanned with search engines
such as InfoSeek, Lycos, Savvy Search, Web Crawler, and Yahoo. Search strategies on
these search engines are listed below. The actual syntax for performing searches varies
for each search engine, so Boolean search descriptors are listed for simplicity:
1. MIL-C-5541 and MIL-C-81706
2. MIL-C-5541 or MIL-C-81706
3. (MIL-C-5541 or MIL-C-81706) and alternative
4. (MIL-C-5541 or MIL-C-81706) and alternative and conversion
5. MIL-C-5541 and chrome and conversion and coating and alternative
6. MIL-C-81706 and chrome and conversion and coating and alternative
7. MIL-C-5541 or MIL-C-81706 or chromium coating
8. MIL-C-5541 and MIL-C-81706 and alternative and chromium and coating
alternative and chrome and coatings.
The relevant articles that were identified during the literature searches are listed in
Section A.4.
A.3. IDENTIFIED ALTERNATIVES
Nine alternative technologies with twenty commercially or near-commercially available
alternative products were identified with the technology survey. A description of each
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identified alternative technology is in this section. The historic test results, and
associated environmental, health, and safety concerns for each identified product are
presented in Appendix B.
Conversion coating is the chemical treatment of metal substrates that produces an
adherent surface coating consisting of substances such as chromates, oxides, or
phosphates. The chemical treatment used during the process depends on the coating
desired. For instance, chrome conversion coatings are produced by combining chromium
compounds (including hexavalent chromium) with other water-soluble inorganic
materials. During the treatment process, the surface of the substrate material (typically
aluminum, cadmium, copper, magnesium, silver, or zinc) is changed to a layer of
chromium salts to produce the desired decorative or functional properties. Decorative
coatings are typically thin coatings that are used as a sealant over phosphate, oxide, or
metallic coatings. Functional coatings are thicker coatings that are commonly used for
corrosion protection. In addition, both decorative and functional chrome conversion
coatings exhibit other favorable attributes, including chemical polishing, low electrical
resistivity, and enhanced bonding of organic finishes to substrates.
Although chrome conversion coating offers many advantageous coating properties, its use
of hexavalent chromium is strictly regulated due to the compound's toxicity and
suspected carcinogenicity. For example, regulations pursuant to the CAA, CWA, and
RCRA contain provisions regulating waste streams from metallic finishing operations
that contain hexavalent chromium. In addition, worker exposure to hexavalent chromium
in the work place is regulated by OSHA through permissible exposure limits. These
regulatory driving forces are increasing manufacturing costs and causing industry to
identify, evaluate, and implement acceptable alternatives for chrome conversion coating.
Several chrome conversion coating alternatives are currently available. Alternatives were
desired that passed at least one of the performance requirements for MIL-C-5541
(Chemical Conversion Coatings on Aluminum and Aluminum Alloys) or MIL-C-81706
(Chemical Conversion Coating Materials for Coating Aluminum and Aluminum Alloys)
concerning corrosion resistance or contact electrical resistance. These alternative
technologies commonly generate less pollution than chrome conversion coating and have
fewer health and safety risks associated with them. Identified alternative technologies for
chrome conversion coating are shown below in Table A-4.
A-4 Potential Alternatives Report
Table A-4. Identified Alternative Technologies
to Chrome Conversion Coating
Alternative Technology
Sol-Gel Coatings
Fluorozirconium Coatings
Cobalt-Based Coatings
Rare Earth Metal Salts
Manganese Oxide Films
Fluotitanic Coatings
Talc Coatings
Anodizing
Proprietary Techniques
Details of the technical, environmental, occupational health, and safety considerations
identified for the alternative technologies are presented below. A brief description of
each identified alternative technology then follows.
A.3.1. Technical Considerations
Each identified alternative technology needs to be assessed for corrosion
resistance, contact electrical resistance, and paint adhesion. These are critical
requirements for Class 1A and Class 3 coatings for MIL-C-5541 and
MIL-C-81706. MIL-C-5541 requires that testing be performed on 2024
aluminum alloy panels for Class 1A coatings. To qualify as a Class 3 coating,
6061 or 2024 aluminum alloys must be used as test panels. A summary of the
corrosion resistance, contact electrical resistance, and paint adhesion requirements
of MIL-C-5541 is provided in Table A-5.
Table A-5. Corrosion Resistance, Contact Electrical Resistance,
and Paint Adhesion Requirements of MIL-C-5541
Coating Corrosion Resistance Contact Electrical Resistance Paint Adhesion
Class 1A 168-Hour N/A Wet Tape
Salt Spray Test Adhesion
<5,000 ?in2 (as applied)
Class 3 168-Hour Wet Tape
<10,000 ?in2 (After Salt Spray
Salt Spray Test Adhesion
Test)
N/A = Not Applicable
MIL-C-81706 requires testing on 2024 and 7075 aluminum alloy panels for Class
1A coatings. Class 3 coatings require testing on 6061 aluminum alloy panels.
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Potential Alternatives Report
Refer to the following table for the corrosion resistance, contact electrical
resistance, and paint adhesion requirements for MIL-C-81706 coatings.
Table A-6. Corrosion Resistance, Contact Electrical Resistance,
and Paint Adhesion Requirements of MIL-C-81706
Coating Corrosion Resistance Contact Electrical Resistance Paint Adhesion
Class 1A 336-Hour N/A Knife and Wet
Salt Spray Test Tape Adhesion
<5,000 ?in (as applied)
2
Class 3 168-Hour Knife and Wet
<10,000 ?in (after salt spray test) Tape Adhesion
2
Salt Spray Test
N/A = Not Applicable
A.3.2. Environmental Issues
Each alternative technology will be governed, to a greater or lesser extent, by
federal environmental laws and regulations. Therefore, a regulatory review of
each alternative was conducted as part of the ESOH analysis. Each alternative
was reviewed to determine the extent of its regulation under the CAA, CWA,
RCRA, the EPCRA, the CERCLA and the Occupational Safety and Health Act.
Alternatives were also compared to the EPA 17 list. Even constituents that are
heavily regulated under one or more of these laws are still available for use by
facilities, although most facilities wisely restrict their use.
A.3.3. Health and Safety Issues
As part of the technology survey, each identified alternative was assessed for
associated occupational health and safety concerns. Each identified constituent of
the alternative, as available, was reviewed in terms of its potential toxicity as a
known or suspected human carcinogen, human genotoxin, human teratogen, or
human neurotoxin. Each of these categories is briefly defined and described
below.
? Human Carcinogen: Those agents, including organic and
inorganic compounds, which have an ability to induce carcinomas
(cancer) in humans are considered human carcinogens. For this
assessment, those constituents which show clear or suspected
evidence of carcinogenic activity in humans as concluded by the
National Toxicology Program (NTP), EPA's Office of Science and
Technology Weight-of Evidence Policy, and/or the International
Agency for Research on Cancer (IARC) guidelines are considered
to be human carcinogens.
A-6 Potential Alternatives Report
? Human Genotoxin: Those agents determined or suspected to be
DNA-reactive (genotoxic), where available information is
sufficient, are considered to be human genotoxins.
? Human Teratogen: Those agents which are determined or
suspected to cause any detrimental effect (structural or functional)
to developing organisms during embryonic development after
exposure (which may occur before conception, during pregnancy,
or directly to the developing organism) are considered to be human
teratogens.
? Human Neurotoxin: Those agents which are determined, or
suspected to cause toxic effects to the human nervous system from
toxic exposure at expected occupational concentrations are
considered to be neurotoxins.
A.3.4. Sol-Gel Coatings
Sol-Gel technology uses polymers or metal oxides either alone or mixed to form
complexes by the hydrolysis of appropriate precursor compounds. The most
appropriate compounds are metal alkoxides. Sol-Gels can form powders or thin
films that can inhibit corrosion on substrates. The Sol-Gel technology is a
potential alternative technology for chrome conversion coatings.
A.3.5. Fluorozirconium Coatings
This technology uses complexed transition metals salts to create a thin film on a
substrate material similar to a conversion coating. Specifically, zirconium is
mixed with fluorine to create fluorozirconium, which reacts with the part surface
to create a coating. Fluorozirconium coatings are a potential alternative
technology to chrome conversion coatings.
A.3.6. Cobalt-Based Coatings
A technology exists which uses cobalt and molybdenum to treat substrate
materials. The coatings created are low in electrical resistance and are good for
corrosion resistance. Cobalt-based coating technology is a potential alternative
technology to chrome conversion coatings.
A.3.7. Rare Earth Metal Salts
The use of rare earth metal salts (REMs) is a potential alternative technology to
chrome conversion coating. As with other coatings, these materials may be
applied by immersion, although the bath requires heating, to create protective
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Potential Alternatives Report
layers on substrate materials. REMs provide corrosion resistance by producing a
protective REM oxide film.
A.3.8. Manganese Oxide Films
Potassium permanganate solutions can be used to create manganese oxide films
on substrates. Since manganese oxides and chromic oxides are very similar, the
manganese oxide films resulting from potassium permanganate treatment closely
matches the corrosion resistance of traditional chromic oxide films used in
conversion coatings. Potassium permanganate coatings are very effective in
protecting aluminum alloys.
A.3.9. Fluotitanic Coatings
Another alternative technology to chrome conversion coating is the use of
fluotitanic acid solutions with organic polymers. This technology requires few
processing steps, and can usually be done at ambient temperatures. Although
these coatings have been widely used in a variety of applications, they have not
been used in the aerospace industry.
A.3.10. Talc Coatings
Talc coatings, which are typically applied to aluminum substrates, are resistant to
corrosion. These polycrystalline coatings are applied by the precipitation of
aluminum-lithium compounds and other anions in an alkaline salt solution. The
outer layers of the resultant coating are porous, but the pores do not reach the
substrate surface. Talc coatings are a good alternative technology for chrome
conversion coating.
A.3.11. Anodizing
Anodizing is a process that produces a tough, adherent surface layer by converting
a metal surface to an oxide layer. A thick oxide layer can be produced by
immersing a part in an electrolytic solution and passing an electrical current
through it, similar to electroplating. The resulting film is nearly colorless, and can
be easily dyed because it is very porous at the molecular level. Then, by placing
the part in boiling water, the film's pores can be sealed; the oxide changes from
one form to another as a result. Several metals such as aluminum, titanium,
niobium, and possibly magnesium and others, can be anodized. Appropriate
current is then applied, i.e., 1.5 amps per decimeter. This lasts 15-25 minutes if
no drying is planned, or 45-60 minutes for dying.
A-8 Potential Alternatives Report
A.3.12. Proprietary Techniques
There are several proprietary techniques that are commercially or near
commercially available. Because these techniques are kept secret, little is known
about the chemical or physical changes that occur in the processing, and therefore
these techniques are grouped together. However, historical data shows that these
techniques have significant value, and since they are available for general use as
possible alternatives to chrome conversion coatings, they are included in this
technology survey. The proprietary processes identified are listed below, and
further information on each can be found in Appendix B.
? Alumicoat 6788 by Elf Atochem
? Chemcote L497260A by Brent America, Inc.
? CFCC by Hughes Aircraft Company
? E-CLPS Coatings from Bulk Chemicals, Inc.
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Potential Alternatives Report
A.4. BIBLIOGRAPHIC INFORMATION
40 CFR ?61.30. July 1, 1994.
Fennessey, Heather E. MTS Technologies, Inc. Chrome Conversion Coating
Alternatives. Technology Abstract. An NDCEE publication. December 1994.
King, Deborah E. Concurrent Technologies Corporation. How the Clean Water Act
Affects You. Water Pollution Control and Existing Direct Dischargers in the
Electroplating Industry. Regulatory Industry Alert. An NDCEE publication. October
1994.
King, Deborah E. Concurrent Technologies Corporation. The Federal Clean Air Act, as
Amended in 1990. Regulatory Overview. An NDCEE publication. July 1994.
Military Specification. Chemical Conversion Coating Materials for Coating Aluminum
and Aluminum Alloys. MIL-C-81706. Amendment 5. November 13, 1979.
Military Specification. Chemical Conversion Coatings on Aluminum and Aluminum
Alloys. MIL-C-5541. November 30, 1990.
Qazi, M. A. Concurrent Technologies Corporation. Chrome-free Conversion Coatings.
State-of-the-Art Technology. An NDCEE publication. February 28, 1994.
Technical Alternatives to Cadmium Electroplating. Phase I Assessment. An NDCEE
publication. Draft. October 1995.
Sehmbhi, T. S.; C. Barnes; and J. J. B Ward, Alternatives to Chrome Conversion
Coatings for Aluminum; Transactions of the Institute of Metal Finishing Vol. 62, Pt. 2 pp.
55-8; Summer 1984, Country of Publication: UK.
Sehmbi, T. S.; C. Barnes; and J. J. B. Ward; Alternatives to Chrome Conversion Coatings
for Zinc and Aluminum, Annual Technical Conference and Exhibition - Institute of Metal
Finishing., Eastbourne, England, May 4, 1984; Published by Institute of Metal Finishing,
Birmingham, England, pp. 45-55.
Hinton, Bruce R. W., Corrosion prevention and chromates. The end of an era?,
Aeronautical Research Lab, Melbourne, Aust; Metal Finishing Vol. 89 No. 10,
October 1991, pp. 15-20.
ECM Newsletter. Information on Environmentally Conscious Manufacturing Processes,
July 1992. Sandia National Labs., Albuquerque, NM. Department of Energy,
Washington, DC. July 1992.
A-10 Potential Alternatives Report
Deitzel, J. and S. J. Spadafora, Evaluation of the Hughes Conversion Coating Touch-Up
Pen, Naval Air Warfare Center Aircraft Div., Warminster, PA. Air Vehicle and Crew
Systems Technology Dept. Final Report. January-June 1993. July 22, 1993.
El-Sharif, M. R.; Y. J. Su; A. Watson; and C. U. Chisholm, Factors Influencing the
Codeposition of Zinc-Chromium Alloys, Proceedings of the AESF Annual Technical
Conference 1993. Published by American Electroplaters & Surface Finishers Society
Inc., Orlando, Florida pp. 1083-1089.
Ward, J. J. B. and C. Barnes, New Developments in the Field of Surface Treatment,
Oberflache Surf. Vol. 23, No. 1, January 1982 pp. 6-9 (Article in German language).
Spadafora, S. J., Non-Chromates Surface Pretreatments for Aluminum (Interim Report.
October 9-June 92), Naval Air Warfare Center Aircraft Div., Warminster, PA. Air
Vehicle and Crew Systems Technology Department. Report No.: NAWCADWAR-
92077-60, August 18, 1992.
Goodman, Sherri Wasserman, Remarks Before the National Security Industrial
Association, National Security Industrial Association, January 19, 1994.
Davenport, A. J.; A. J. Aldykiewicz; H. S. Isaacs; M. W. Kendig; A. M. Mundy
XANES Studies of Chrome Replacements in Oxide Films on Aluminum, Meeting of the
Electrochemical Society (180th), Phoenix, AZ (United States), October 13-18, 1991.
Sponsored by Department of Energy, Washington, DC.; Report No.: BNL-47017;
CONF-911047-13; 1991.
Chrome-Free Aluminum Treatment, Advances in Materials and Coatings: An ALERT
Service from Technical Insights, Inc.; Technical Insights: March 5, 1993.
Mansfeld, F.; S. Lin; S. Kim; H. Shih; Corrosion Protection of Al Alloys and Al-based
Metal Matrix Composites by Chemical Passivation; Dept. of Mater. Sci. & Eng., Univ. of
Southern California, Los Angeles, CA, USA; Vol. 45, No. August 8, 1989; pp. 615-29.
Mansfeld, F.; Environmentally-Induced Passivity of Aluminum Alloys and Aluminum
Metal Matrix Composites, University of Southern California, Los Angeles. Dept. of
Materials Science and Engineering; Final report. October 1 - September 30, 1990;
December 1990.
Mansfeld, F.; S. Lin; S. Kim; H. Shih; Pitting and Passivation of Al Alloys and Al-based
Metal Matrix Composites, Dept. of Mater. Sci. & Eng., Univ. of Southern California, Los
Angeles, CA, USA; Journal of the Electrochemical Society Vol. 137, No. 1,
January 1990, pp 78-82.
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Davenport, A. J. and H. S. Isaacs; X-Ray Absorption Study of Cerium in the Passive Film
on Aluminum, Brookhaven Nat. Lab., Upton, New York; Journal of the Electrochemical
Society Vol. 136, No. 6, June 1989; pp. 1837-8.
Chang, F.; M. Levy; and R. Huie; Assessment of Chrome and Non-Chrome Conversion
Coatings for Al Alloys Using Electrochemical Impedance Spectroscopy (Final report),
Army Research Lab., Watertown, MA; Report No.: ARL-TR-142; June 1993.
Buchheit, R. G. and G. E. Stoner; Chrome-free Corrosion Resistant Conversion Coatings
for Aluminum, Sandia National Labs., Albuquerque, New Mexico, Virginia Univ.,
Charlottesville, Virginia. Dept. of Materials Science and Engineering. Department of
Energy (DOE) Compatibility, Aging and Service Life Conference (18th), Aiken, South
Carolina, 20-22, April 1993. Sponsored by Department of Energy, Washington, DC.
1993.
Buchheit, R. G. and G. E. Stoner; Chrome-free Corrosion Resistant Talc Coatings for
Aluminum Alloys; Sandia National Labs., Albuquerque, New Mexico. Electrochemical
Society Meeting (183rd), Honolulu, Hawaii, May 16-21, 1993. Sponsored by Department
of Energy, Washington, DC. 1992.
Buchheit, R. G.; C. A. Drewien; and G. E. Stoner; Chrome-free Talc Chemical
Conversion Coatings for Aluminum Alloys, Electrochemical Society Meeting (183rd),
Honolulu, Hawaii, May 16-21, 1993. Sponsored by Department of Energy, Washington,
DC. 1993.
Buchheit, R. G.; C. A. Drewien; and J. L. Finch; Non-chrome Talc Conversion Coatings;
Corrosion 94: National Association of Corrosion Engineers (NACE) International Annual
Conference, Baltimore, Maryland, February 28-March 4, 1994. Sponsored by
Department of Energy, Washington, DC., 1994.
A-12 Potential Alternatives Report
APPENDIX B
PRODUCT IDENTIFICATION
TABLE OF CONTENTS
Page
B.1. INTRODUCTION......................................................................................................... B-1
B.2. SOL-GEL COATINGS................................................................................................. B-2
B.2.1. Aeroglaze (Lord Corporation)............................................................................. B-2
B.2.1.1. Technical Considerations ........................................................................ B-2
B.2.1.2. Environmental Issues .............................................................................. B-3
B.2.1.3. Health and Safety Issues.......................................................................... B-3
B.2.1.4. Additional Supporting Literature ............................................................ B-4
B.3. FLUOROZIRCONIUM COATINGS ......................................................................... B-5
B.3.1. Alcoat 1470 (Circle-Prosco, Inc.)........................................................................ B-5
B.3.1.1. Technical Considerations ........................................................................ B-5
B.3.1.2. Environmental Issues .............................................................................. B-6
B.3.1.3. Health and Safety Issues.......................................................................... B-6
B.3.1.4. Additional Supporting Literature ............................................................ B-7
B.3.2. Alcoat 3000 (Circle-Prosco, Inc.)........................................................................ B-7
B.3.2.1. Technical Considerations ........................................................................ B-8
B.3.2.2. Environmental Issues .............................................................................. B-8
B.3.2.3. Health and Safety Issues.......................................................................... B-9
B.3.2.4. Additional Supporting Literature ............................................................ B-9
B.3.3. Alcoat 4000 (Circle-Prosco, Inc.)...................................................................... B-10
B.3.3.1. Technical Considerations ...................................................................... B-11
B.3.3.2. Environmental Issues ............................................................................ B-11
B.3.3.3. Health and Safety Issues........................................................................ B-11
B.3.3.4. Additional Supporting Literature .......................................................... B-12
B.3.4. Alcoat 5000 (Circle-Prosco, Inc.)...................................................................... B-13
B.3.4.1. Technical Considerations ...................................................................... B-13
B.3.4.2. Environmental Issues ............................................................................ B-14
B.3.4.3. Health and Safety Issues........................................................................ B-14
B.3.4.4. Additional Supporting Literature .......................................................... B-15
B.4. COBALT-BASED COATINGS ................................................................................. B-16
B.4.1. Alodine 2000 (Parker Amchem) ....................................................................... B-16
B.4.1.1. Technical Considerations ...................................................................... B-16
B.4.1.2. Environmental Issues ............................................................................ B-17
B.4.1.3. Health and Safety Issues........................................................................ B-18
B.4.1.4. Additional Supporting Literature .......................................................... B-19
B.5. RARE EARTH METAL SALTS............................................................................... B-21
B.5.1. Ce-Mo 6061 (University of Southern California) ............................................. B-21
B.5.1.1. Technical Considerations ...................................................................... B-22
B.5.1.2. Environmental Issues ............................................................................ B-22
Potential Alternatives Report B-i
B.5.1.3. Health and Safety Issues........................................................................ B-23
B.5.1.4. Additional Supporting Literature .......................................................... B-23
B.6. MANGANESE OXIDE FILMS ................................................................................. B-25
B.6.1. Patclin 1910B (Patclin Chemical Company, Inc.)............................................. B-25
B.6.1.1. Technical Considerations ...................................................................... B-25
B.6.1.2. Environmental Issues ............................................................................ B-26
B.6.1.3. Health and Safety Issues........................................................................ B-26
B.6.1.4. Additional Supporting Literature .......................................................... B-27
B.6.2. Sanchem FP (Sanchem) .................................................................................... B-27
B.6.2.1. Technical Considerations ...................................................................... B-28
B.6.2.2. Environmental Issues ............................................................................ B-29
B.6.2.3. Health and Safety Issues........................................................................ B-30
B.6.2.4. Additional Supporting Literature .......................................................... B-31
B.7. FLUOTITANIC COATINGS .................................................................................... B-33
B.7.1. Permatreat 611 (Betz Laboratories)................................................................... B-33
B.7.1.1. Technical Considerations ...................................................................... B-33
B.7.1.2. Environmental Issues ............................................................................ B-34
B.7.1.3. Health and Safety Issues........................................................................ B-34
B.7.1.4. Additional Supporting Literature .......................................................... B-34
B.8. TALC COATINGS ..................................................................................................... B-36
B.8.1. Sandia 1 and Sandia 2 (Sandia National Laboratories) ..................................... B-36
B.8.1.1. Technical Considerations ...................................................................... B-36
B.8.1.2. Environmental Issues ............................................................................ B-37
B.8.1.3. Health and Safety Issues........................................................................ B-38
B.8.1.4. Additional Supporting Literature .......................................................... B-38
B.9. ANODIZING ............................................................................................................... B-39
B.9.1. Sulfuric-Boric Acid Anodizing (Boeing Aerospace Corporation).................... B-39
B.9.1.1. Technical Considerations ...................................................................... B-39
B.9.1.2. Environmental Issues ............................................................................ B-40
B.9.1.3. Health and Safety Issues........................................................................ B-40
B.9.1.4. Additional Supporting Literature .......................................................... B-41
B.9.2. Alumitec (Alumitec Products Corporation) ...................................................... B-42
B.9.2.1. Technical Considerations ...................................................................... B-43
B.9.2.2. Environmental Issues ............................................................................ B-44
B.9.2.3. Health and Safety Issues........................................................................ B-44
B.9.2.4. Additional Supporting Literature .......................................................... B-44
B.10. PROPRIETARY TECHNIQUES.............................................................................. B-46
B.10.1. Alumicoat 6788 (Elf Atochem - Turco Products Division) .............................. B-46
B.10.1.1. Technical Considerations ...................................................................... B-46
B.10.1.2. Environmental Issues ............................................................................ B-47
B.10.1.3. Health and Safety Issues........................................................................ B-47
B-ii Potential Alternatives Report
B.10.1.4. Additional Supporting Literature .......................................................... B-48
B.10.2. Chemcote L497260A (Brent America, Inc.) ..................................................... B-49
B.10.2.1. Technical Considerations ...................................................................... B-49
B.10.2.2. Environmental Issues ............................................................................ B-50
B.10.2.3. Health and Safety Issues........................................................................ B-50
B.10.2.4. Additional Supporting Literature .......................................................... B-51
B.10.3. Chrome-Free Conversion Coating (Hughes Aircraft Company)....................... B-51
B.10.3.1. Technical Considerations ...................................................................... B-53
B.10.3.2. Environmental Issues ............................................................................ B-53
B.10.3.3. Health and Safety Issues........................................................................ B-53
B.10.3.4. Additional Supporting Literature .......................................................... B-55
B.10.4. E-CLPS 923 and E-CLPS 923X (Bulk Chemicals, Inc.) .................................. B-56
B.10.4.1. Technical Considerations ...................................................................... B-56
B.10.4.2. Environmental Issues ............................................................................ B-57
B.10.4.3. Health and Safety Issues........................................................................ B-57
B.10.4.4. Additional Supporting Literature .......................................................... B-58
B.10.5. Turco 2438-28D (Elf Atochem - Turco Products Division) ............................. B-59
B.10.5.1. Technical Considerations ...................................................................... B-59
B.10.5.2. Environmental Issues ............................................................................ B-60
B.10.5.3. Health and Safety Issues........................................................................ B-60
B.10.5.4. Additional Supporting Literature .......................................................... B-60
LIST OF TABLES
Page
Table B-1. PELs and TLVs for Chemicals in Alcoat 1470 Process...................................... B-6
Table B-2. PELs and TLVs for Chemicals of Alcoat 3000................................................... B-9
Table B-3. PELs and TLVs for Chemicals in Alcoat 4000 Process.................................... B-12
Table B-4. PELs and TLVs for Chemicals in Alcoat 5000 Process.................................... B-14
Table B-5. PELs and TLVs for Chemicals in Alodine 2000 Process.................................. B-18
Table B-6. Chemical Products of Alodine 2000 Process .................................................... B-18
Table B-7. PELs and TLVs for Chemicals in Ce-Mo 6061 Process ................................... B-23
Table B-8. PELs and TLVs for Chemicals in Patclin 1910B Process................................. B-26
Table B-9. PELs and TLVs for Chemicals in Sanchem FP Process ................................... B-30
Table B-10. Chemical Products of Sanchem FP Process ...................................................... B-30
Table B-11. PELs and TVLs for Chemicals in Permatreat 611 Process ............................... B-34
Table B-12. PELs and TVLs for Chemicals in SBAA Process............................................. B-41
Table B-13. Chemical Products of Alumicoat 6788 Process ................................................ B-47
Table B-14. PELs and TVLs for Chemicals in Chemote L497260A Process....................... B-50
Table B-15. PELs and TVLs for Chemicals in CFCC Process ............................................. B-54
Table B-16. Chemical Products of CFCC Process................................................................ B-54
Table B-17. PELs and TLVs for Chemicals in E-CLPS 923 and E-CLPS 923X
Processes ........................................................................................................... B-58
Potential Alternatives Report B-iii
B.1. INTRODUCTION
From information gathered in the technology survey in 1995, available products and
processes were identified for each of the identified technologies. Product specific
information for each alternative product, including general process information, is
provided in Sections B.2 through B.10. In addition, technical considerations,
environmental issues, and health and safety issues that concern each alternative are
discussed in each section.
Touch-up techniques for parts that are scratched while in use are also discussed for each
alternative. When available, any other pertinent information, such as abrasion resistance,
is also provided.
Potential Alternatives Report B-1
B.2. SOL-GEL COATINGS
Though there are many types of Sol-Gel coatings, only one was found to have relevant
historical test results.
B.2.1. Aeroglaze (Lord Corporation)
The Aeroglaze Sol-Gel process, patented by Lord Corporation, varies slightly
from typical Sol-Gel processes that use polymers to cast a coating. The patented
process treats parts by immersing them into a bath, much like anodizing or
phosphatizing processes. The overall process is as follows:
1. Cleaning and Rinsing: This step removes bulk contaminants such
as thick wax.
2. Sol-Gel Process: The part is dipped into a bath that consists of
70% alcohol (e.g., ethanol), 25% water, 2-3% ammonium
hydroxide catalyst, and the remainder as tetraethoxysilane (TEOS).
This bath make-up may be varied, depending on the end
application (as required for a paintable or nonpaintable surface).
The make-up listed above is for corrosion protection applications.
The part is then removed from the bath after allowing it to react for
5 to 20 minutes.
3. Drying: Parts can be dried with a variety of methods, including
hanging, blowing, or oven drying.
The reaction that proceeds during the Sol-Gel process converts the surface metal
oxide layer to a silicon oxide layer. For example, aluminum parts would form an
aluminum silicate coating on the surface. The resultant coating is a glass layer
that is 1,000 Angstroms (? (0.004 mils) thick.
B.2.1.1. Technical Considerations
National Center for Manufacturing Sciences (NCMS) issued a study
(NCMS, 1995) that compared nonchromate conversion coatings to
Alodine 600 and 1200 series coatings (chrome conversion coatings
manufactured by Parker Amchem) on aluminum substrates. Among the
alternatives tested was a paintable Aeroglaze Sol-Gel coating. Below is a
summary of the findings.
? Corrosion Resistance: Aeroglaze Sol-Gel coatings passed
corrosion resistance tests on aluminum alloy 6061.
However, they did not pass tests on alloys 2024 and 7075.
Tests followed MIL-C-5541 procedures.
B-2 Potential Alternatives Report
? Contact Electrical Resistance: Aeroglaze Sol-Gel coatings
passed contact electrical resistance tests on alloy 6061
before a salt spray. Tests followed MIL-C-81706
procedures. Substrates coated with Aeroglaze Sol-Gel were
also tested until failure after a salt spray. The coatings had
a mean contact electrical resistance of 49.3 m/in2.
? Paint Adhesion: Aeroglaze Sol-Gel coatings passed the dry
paint adhesion test on alloy 6061, but failed the wet paint
adhesion test on that alloy. They failed dry and wet paint
adhesion tests on alloys 2024 and 7075. Tests followed
MIL-C-5541 and MIL-C-81706 procedures.
Although the Sol-Gel coatings offer corrosion resistance and a good
bonding surface, they offer little abrasion resistance. A formal procedure
for touch-up is not in place; however, various techniques for touch-up may
be successful (e.g., a chrome pen).
Aeroglaze Sol-Gel coatings recently became available commercially. Lord
Corporation is currently searching for facilities that would like to test these
coatings in actual production. However, Lord Corporation is not currently
manufacturing these coatings on a full-scale production line.
B.2.1.2. Environmental Issues
The constituents of the Aeroglaze Sol-Gel baths are not listed as one of the
189 hazardous air pollutants (HAPs) under Title III of the Clean Air Act
(CAA), as amended in 1990. In addition, they are not considered to be
ozone-depleting substances (ODSs). Sludge from this process may be
required to be managed in accordance with the requirements of Subtitle C
of the Resource Conservation and Recovery Act (RCRA).
B.2.1.3. Health and Safety Issues
Only one constituent in these processes is listed by OSHA as an airborne
contaminant that must be regulated with PELs; ethanol must be
maintained below 1,000 ppm. In addition, the ACGIH recommends a PEL
of 1,000 ppm for ethanol. Ventilation may be required to maintain
airborne ethanol below these concentrations. It should be noted that
ethanol is a known human carcinogen via oral exposure, as well as a
known human teratogen, genotoxin, and neurotoxin. Methanol is a
suspected human teratogen and genotoxin (human data reported), as well
as a known human neurotoxin. Methanol is listed on EPA's Genetic
Toxicity Program.
Potential Alternatives Report B-3
B.2.1.4. Additional Supporting Literature
? ACGIH, 1995, Industrial Ventilation: A Manual of
Recommended Practice. 22nd ed. Cincinnati, OH.
? ACGIH, 1991, Documentation of the Threshold Limit
Values and Biological Exposure Indices. 6th ed. Vols I-III.
Cincinnati, OH.
? Ferrell, Victor. Lord Corporation. Telephone
Conversation. April 9, 1996.
? Holmes-Farley, Stephen R.; Lynn Yanyo; and Anna M.
Thuer. Lord Corporation. Method for Metal Bonding.
Patent 5139601. August 18, 1992.
? Holmes-Farley, Stephen R. and Lynn C. Yanyo. Layered
Sol-Gel Coatings. Patent 5,182,143. January 26, 1993.
? Holmes-Farley, Stephen R. and Lynn C. Yanyo. Ultra-
Thin, Uniform Sol-Gel Coatings. Patent 5,175,027.
December 29, 1992.
? Lewis, Richard J., Sr., 1992, Sax's Dangerous Properties of
Industrial Materials. 8th ed. Vols I-III. Van Nostrand
Reinhold, New York.
? MDS Information Systems Inc., 1996, OHS MSDS on Disk.
? National Center for Manufacturing Sciences, 1995,
Alternatives to Chromium for Metal Finishing, Ann Arbor,
Michigan.
? NIOSH, 1994, NIOSH Pocket Guide to Chemical Hazards.
U.S. Government Printing Office, Washington, DC.
? Yanyo, Lynn. Lord Corporation. Telephone Conversation.
November 14, 1995.
? 40 CFR part 261 et seq.
? 40 CFR part 400 et seq.
? 40 CFR part 129 et seq.
? 42 USC ?412(b)
Point of Contact
For Technical Inquiries: For Marketing Inquiries:
Lynn Yanyo Victor Ferrell
Lord Corporation Lord Corporation
405 Gregson Drive Phone: 919-859-3034, x6315
Cary, NC 27511
Phone: 919-469-3443, x329
Fax: 919-460-9648
B-4 Potential Alternatives Report
B.3. FLUOROZIRCONIUM COATINGS
Circle-Prosco, Inc. provides a family of products using fluorozirconium coating
technology for a wide range of applications. Four such products are described in the
following sections.
B.3.1. Alcoat 1470 (Circle-Prosco, Inc.)
Alcoat 1470, manufactured by Circle-Prosco, Inc., uses complexed transition
metal salts to treat parts. To treat parts with this product, the steps listed below
are performed.
1. Cleaning: One cleaning agent that can be used for cleaning is
Alcoat 1470C. However, other cleaners may be appropriate for
specific applications. Alcoat 1470C contains nitric acid,
hydrofluoric acid, and zirconium salt.
2. Water Rinsing
3. Conversion Coating with Alcoat 1470B: Alcoat 1470B also
contains nitric acid, hydrofluoric acid, and zirconium salt. It is
maintained between 70癋 and 150癋.
4. Water Rinsing
5. Sealing: Alcoat 1470S is recommended by Circle-Prosco, Inc.
Alcoat 1470S contains potassium hydroxide. It is maintained
between 70癋 and 150癋.
6. Drying: After conversion coating, parts are oven dried for
10 minutes at 250癋.
B.3.1.1. Technical Considerations
NCMS issued a study that compared nonchromate conversion coatings to
Alodine 600 and 1200 series coatings (chrome conversion coatings
manufactured by Parker Amchem) on aluminum substrates. Among the
alternatives tested was Alcoat 1470. Below is a summary of the findings.
? Corrosion Resistance: Alcoat 1470 passed corrosion
resistance tests on aluminum alloy 6061. However, it failed
tests on aluminum alloy 2024 and alloy 7075. Tests
followed MIL-C-5541 procedures.
? Contact Electrical Resistance: Alcoat 1470 failed contact
electrical resistance tests on alloy 6061 before a salt spray.
Tests followed MIL-C-81706 procedures. Substrates
coated with Alcoat 1470 were also tested until failure after
a salt spray. The coatings had a mean contact electrical
resistance of 426 m/in2.
Potential Alternatives Report B-5
? Paint Adhesion: Alcoat 1470 failed dry and wet paint
adhesion tests on aluminum alloys 2024, 6061, and 7075.
Tests followed MIL-C-5541 and MIL-C-81706 procedures.
Circle-Prosco, Inc. is currently performing salt spray tests with scratched
and re-coated panels. It is expected that coatings with a scratch to the bare
metal can be repaired by brushing on the Alcoat 1470 solution with a paint
brush. After Alcoat 1470 coating is dry, it must be repainted.
B.3.1.2. Environmental Issues
The Alcoat 1470 process, specifically Alcoat 1470B, contains two
chemicals that are regulated as HAPs under Title III of the CAA. Due to
the acidic and basic nature of the wastewaters from the Alcoat 1470
process, the wastewater must be neutralized to meet Clean Water Act
(CWA) permitting guidelines for the Metal Finishing Point Source
category. Sludge from this process may be required to be managed in
accordance with the requirements of RCRA
Subtitle C.
B.3.1.3. Health and Safety Issues
OSHA has set PELs and the ACGIH has set TLVs for chemicals in the
Alcoat 1470 process, as listed in Table B-1.
Table B-1. PELs and TLVs for Chemicals in Alcoat 1470
Process
Chemical OSHA PEL ACGIH TLV
Nitric Acid 2 ppm 2 ppm
Hydrofluoric Acid 3 ppm, as F 3 ppm, as F
(Ceiling)
2 mg/m3
Potassium Hydroxide None
NIOSH: 2 mg/m3 (Ceiling)
Ventilation is required to maintain airborne contaminants below the PELs
and TLVs. In addition, personal protection, such as goggles, neoprene
rubber gloves, and respirators, is required. No suspected human
carcinogens, genotoxins or neurotoxins are present in the Alcoat 1470
process. However, it should be noted that nitric acid and hydrofluoric acid
are experimental animal teratogens. Hydrofluoric acid appears in EPA's
Genetic Toxicology Program.
B-6 Potential Alternatives Report
B.3.1.4. Additional Supporting Literature
? ACGIH, 1995, Industrial Ventilation: A Manual of
Recommended Practice. 22nd ed. Cincinnati, OH.
? ACGIH, 1991, Documentation of the Threshold Limit
Values and Biological Exposure Indices. 6th ed. Vols I-III.
Cincinnati, OH.
? Lewis, Richard J., Sr., 1992, Sax's Dangerous Properties of
Industrial Materials. 8th ed. Vols I-III. Van Nostrand
Reinhold, New York.
? Manard, Jack. Circle-Prosco, Inc. Telephone Conversation.
November 20, 1995.
? MSDS Information Systems, Inc., 1996, OHS MSDS on
Disk.
? National Center for Manufacturing Sciences, 1995,
Alternatives to Chromium for Metal Finishing, Ann Arbor,
Michigan.
? NIOSH, 1994, NIOSH Pocket Guide to Chemical Hazards.
U.S. Government Printing Office, Washington, DC.
? Parker, Doug. Circle-Prosco, Inc. Telephone
Conversation. November 22, 1995 and April 3, 1996.
? 40 CFR part 261 et seq.
? 40 CFR part 400 et seq.
? 40 CFR part 129 et seq.
? 42 USC ?412(b)
Point of Contact
General Inquiries: Technical Inquiries:
Jack Manard Doug Parker
Circle-Prosco, Inc. Phone: 812-339-3653
2017 Yost Avenue Fax: 812-331-2566
Bloomington, IN 47403
Phone: 317-579-5353
Fax: 317-579-5354
B.3.2. Alcoat 3000 (Circle-Prosco, Inc.)
Alcoat 3000, manufactured by Circle-Prosco, Inc., uses complexed transition
metal salts to treat parts. To treat parts with this chemical, the steps listed below
are performed.
Potential Alternatives Report B-7
1. Cleaning: One cleaning agent that can be used is Alcoat 3000C.
However, other cleaners may be appropriate, depending on the
specific application.
2. Water Rinsing
3. Conversion Coating with Alcoat 3000B
4. Water Rinsing
5. Drying: After conversion coating, parts are oven dried for
10 minutes at 250癋.
B.3.2.1. Technical Considerations
NCMS issued a study that compared nonchromate conversion coatings to
Alodine 600 and 1200 series coatings (chrome conversion coatings
manufactured by Parker Amchem) on aluminum substrates. Among the
alternatives tested was Alcoat 3000. Below is a summary of the findings
? Corrosion Resistance: Alcoat 3000 passed corrosion
resistance tests on aluminum alloy 6061. However, it failed
tests on aluminum alloys 2024 and 7075. Tests followed
MIL-C-5541 procedures.
? Contact Electrical Resistance: Alcoat 3000 failed contact
electrical resistance tests on alloy 6061 before a salt spray.
Tests followed MIL-C-81706 procedures. Substrates
coated with Alcoat 3000 were also tested until failure after
a salt spray. The coatings had a mean contact electrical
resistance of 644 m/in2.
? Paint Adhesion: Alcoat 3000 passed dry and wet paint
adhesion tests on aluminum alloys 6061 and 7075. It also
passed the dry paint adhesion test for alloy 2024; however,
it failed the wet paint adhesion test on that alloy. Tests
followed MIL-C-5541 and MIL-C-81706 procedures.
Circle-Prosco, Inc. is currently performing salt spray tests with scratched
and re-coated panels. It is expected that coatings with a scratch to the bare
metal can be repaired by brushing on the Alcoat 3000 solution with a paint
brush. After Alcoat 3000 coating is dry, it must be repainted.
B.3.2.2. Environmental Issues
The Alcoat 3000 process, specifically Alcoat 3000B, contains one
chemical that is regulated as a HAP under Title III of the CAA. Due to the
acidic and basic nature of the wastewater from the Alcoat 3000 process,
the wastewater must be neutralized to meet CWA permitting guidelines
B-8 Potential Alternatives Report
for the Metal Finishing Point Source category. Sludge from this process
may be required to be managed in accordance with the requirements of
RCRA Subtitle C.
B.3.2.3. Health and Safety Issues
OSHA has set PELs and the ACGIH has set TLVs for chemicals in the
Alcoat 3000 process, as listed in Table B-2 below.
Table B-2. PELs and TLVs for Chemicals of Alcoat 3000
Chemical OSHA PEL ACGIH TLV
5 mg/m3
Sodium Tripolyphosphate None
Hydrofluoric Acid 3 ppm, as F 3 ppm, as F (Ceiling)
2.5 mg/m3, as F 2.5 mg/m3, as F
Fluoride Salt
Ventilation is required to maintain airborne contaminants below the PELs
and TLVs. In addition, personal protection, such as goggles, gloves, and
respirators, is required. No suspected human carcinogens, genotoxins or
neurotoxins are present in the Alcoat 3000 process. However,
hydrofluoric acid is an experimental animal teratogen and appears in
EPA's Genetic Toxicology Program.
B.3.2.4. Additional Supporting Literature
? ACGIH, 1995, Industrial Ventilation: A Manual of
Recommended Practice. 22nd ed. Cincinnati, OH.
? ACGIH, 1991, Documentation of the Threshold Limit
Values and Biological Exposure Indices. 6th ed. Vols I-III.
Cincinnati, OH.
? Lewis, Richard J., Sr., 1992, Sax's Dangerous Properties of
Industrial Materials. 8th ed. Vols I-III. Van Nostrand
Reinhold, New York.
? Manard, Jack. Circle-Prosco, Inc. Telephone
Conversation. November 20, 1995.
? MSDS Information Systems Inc., 1996, OHS MSDS on
Disk.
? National Center for Manufacturing Sciences, 1995,
Alternatives to Chromium for Metal Finishing, Ann Arbor,
Michigan.
? NIOSH, 1994, NIOSH Pocket Guide to Chemical Hazards.
U.S. Government Printing Office, Washington, DC.
Potential Alternatives Report B-9
? Parker, Doug. Circle-Prosco, Inc. Telephone
Conversation. November 22, 1995 and April 3, 1996.
? 40 CFR part 261 et seq.
? 40 CFR part 400 et seq.
? 40 CFR part 129 et seq.
? 42 USC ?412(b)
Point of Contact
General Inquiries: Technical Inquiries:
Jack Manard Doug Parker
Circle-Prosco, Inc. Phone: 812-339-3653
2017 Yost Avenue Fax: 812-331-2566
Bloomington, IN 47403
Phone: 317-579-5353
Fax: 317-579-5354
B.3.3. Alcoat 4000 (Circle-Prosco, Inc.)
Alcoat 4000, manufactured by Circle-Prosco, Inc., uses complexed transition
metal salts to treat parts. To treat parts with this chemical, the steps listed below
are performed.
1. Cleaning: One cleaning agent that may be used is Alcoat 4000C.
However, other cleaners may be appropriate for specific
applications. Alcoat 4000C contains sodium tripolyphosphate.
2. Water Rinsing
3. Etching: Etching may be performed with Alcoat 4000B, which
contains nitric acid and hydrofluoric acid.
4. Water Rinsing
5. Conversion Coating with Alcoat 4000B1: Alcoat 4000B1 contains
nitric acid, hydrofluoric acid, and a zirconium salt.
6. Water Rinsing
7. Sealing: Circle-Prosco, Inc. recommends using Alcoat 4000S as a
sealant. Alcoat 4000S contains potassium hydroxide.
8. Drying: After conversion coating, parts are oven dried for
10 minutes at 250癋.
All process steps are at ambient temperature, except for sealing, which is
maintained at 120癋.
B-10 Potential Alternatives Report
B.3.3.1. Technical Considerations
NCMS issued a study that compared nonchromate conversion coatings to
Alodine 600 and 1200 series coatings (chrome conversion coatings
manufactured by Parker Amchem) on aluminum substrates. Among the
alternatives tested was Alcoat 4000. Below is a summary of the findings
? Corrosion Resistance: Alcoat 4000 exceeded corrosion
resistance tests for aluminum alloy 6061. However, it
failed tests on aluminum alloys 2024 and 7075. Tests
followed
MIL-C-5541 procedures.
? Contact Electrical Resistance: Alcoat 4000 failed contact
electrical resistance tests on alloy 6061 before a salt spray.
Tests followed MIL-C-81706 procedures. Substrates
coated with Alcoat 4000 were also tested until failure after
a salt spray. The coatings had a mean contact electrical
resistance of 376,000 m/in2.
? Paint Adhesion: Alcoat 4000 failed dry and wet paint
adhesion tests on aluminum alloys 2024, 6061, and 7075.
Tests followed MIL-C-5541 and MIL-C-81706 procedures.
Circle-Prosco, Inc. is currently performing salt spray tests with scratched
and re-coated panels. It is expected that coatings with a scratch to the bare
metal can be repaired by brushing on the Alcoat 4000 solution with a paint
brush. After Alcoat 4000 coating is dry, it must be repainted.
B.3.3.2. Environmental Issues
The Alcoat 4000 process contains two chemicals that are regulated as
HAPs under Title III of the CAA. The HAPs are present in Alcoat 4000B
and Alcoat 4000B1. Due to the acidic and basic nature of the wastewater
from the Alcoat 4000 process, the wastewater must be neutralized to meet
CWA permitting guidelines for the Metal Finishing Point Source category.
Sludge from this process may be required to be managed in accordance
with the requirements of RCRA Subtitle C.
B.3.3.3. Health and Safety Issues
OSHA has set PELs and the ACGIH has set TLVs for chemicals in the
Alcoat 4000 process, as listed in Table B-3.
Potential Alternatives Report B-11
Table B-3. PELs and TLVs for Chemicals in Alcoat 4000
Process
Chemical OSHA PEL ACGIH TLV
5 mg/m3
Sodium Tripolyphosphate None
Nitric Acid 2 ppm 2 ppm
Hydrofluoric Acid 3 ppm, as F 3 ppm, as F
(Ceiling)
2 mg/m3
Potassium Hydroxide None
NIOSH: 2 mg/m3 (Ceiling)
Ventilation is required to maintain airborne contaminants below the PELs
and TLVs. In addition, personal protection, such as goggles, rubber
gloves, and respirators, is required. No suspected human carcinogens,
genotoxins or neurotoxins are present in the Alcoat 4000 process.
However, nitric acid and hydrofluoric acid are experimental animal
teratogens and hydrofluoric acid appears in the EPA's Genetic Toxicology
Program.
B.3.3.4. Additional Supporting Literature
? ACGIH, 1995, Industrial Ventilation: A Manual of
Recommended Practice. 22nd ed. Cincinnati, OH.
? ACGIH, 1991, Documentation of the Threshold Limit
Values and Biological Exposure Indices. 6th ed. Vols I-III.
Cincinnati, OH.
? Manard, Jack. Circle-Prosco, Inc. Telephone
Conversation. November 20, 1995.
? Lewis, Richard J., Sr., 1992, Sax's Dangerous Properties of
Industrial Materials. 8th ed. Vols I-III. Van Nostrand
Reinhold, New York.
? MSDS Information Systems Inc., 1996, OHS MSDS on
Disk.
? National Center for Manufacturing Sciences, 1995,
Alternatives to Chromium for Metal Finishing, Ann Arbor,
Michigan.
? NIOSH, 1994, NIOSH Pocket Guide to Chemical Hazards.
U.S. Government Printing Office, Washington, DC.
? Parker, Doug. Circle-Prosco, Inc. Telephone
Conversation. November 22, 1995 and April 3, 1996.
? 40 CFR part 261 et seq.
? 40 CFR part 400 et seq.
B-12 Potential Alternatives Report
? 40 CFR part 129 et seq.
? 42 USC ?412(b)
Point of Contact
General Inquiries: Technical Inquiries:
Jack Manard Doug Parker
Circle-Prosco, Inc. Phone: 812-339-3653
2017 Yost Avenue Fax: 812-331-2566
Bloomington, IN 47403
Phone: 317-579-5353
Fax: 317-579-5354
B.3.4. Alcoat 5000 (Circle-Prosco, Inc.)
As with Alcoat 1470, 3000, and 4000, Alcoat 5000 treats parts by using a
zirconium-based conversion coating process. When using Alcoat 5000 as a
chrome conversion coating alternative, several process steps must be performed
for an adequate coating. These steps are listed below.
1. Cleaning: Cleaning may be performed with Alcoat 5000C, which
contains sodium tripolyphosphate. However, other cleaners may
be appropriate depending on the specific applications.
2. Water Rinsing
3. Conversion Coating with Alcoat 5000B: This bath contains
hydrofluoric acid, a fluoride salt, and a zirconium salt.
4. Water Rinsing
5. Sealing: Circle-Prosco, Inc. recommends that sealing be
performed with Alcoat 5000S. This bath, which contains
potassium hydroxide, is maintained at 120癋.
6. Drying: After conversion coating, parts are oven dried for
10 minutes at 250癋.
B.3.4.1. Technical Considerations
NCMS issued a study that compared nonchromate conversion coatings to
Alodine 600 and 1200 series coatings (chrome conversion coatings
manufactured by Parker Amchem) on aluminum substrates. Among the
alternatives tested was Alcoat 5000. Below is a summary of the findings.
? Corrosion Resistance: Alcoat 5000 failed corrosion
resistance tests on aluminum alloys 2024, 6061, and 7075.
Tests followed MIL-C-5541 procedures.
Potential Alternatives Report B-13
? Contact Electrical Resistance: Alcoat 5000 passed contact
electrical resistance tests on alloy 6061 before a salt spray.
Tests followed MIL-C-81706 procedures. Substrates
coated with Alcoat 5000 were also tested until failure after
a salt spray. The coatings had a mean contact electrical
resistance of 137 m/in2.
? Paint Adhesion: Alcoat 5000 passed dry paint adhesion
tests on aluminum alloys 2024 and 7075. However, it
failed the dry paint adhesion test on alloy 6061, and failed
wet paint adhesion tests on alloys 2024, 6061, and 7075.
Tests followed MIL-C-5541 and MIL-C-81706 procedures.
Circle-Prosco, Inc. is currently performing salt spray tests with scratched
and re-coated panels. It is expected that coatings with a scratch to the bare
metal can be repaired by brushing on the Alcoat 5000 solution with a paint
brush. After Alcoat 5000 coating is dry, it must be repainted.
B.3.4.2. Environmental Issues
The Alcoat 5000 process, specifically Alcoat 5000B, contains one
chemical that is regulated as a HAP under Title III of the CAA. Due to the
acidic and basic nature of the wastewater from the Alcoat 5000 process,
the wastewater must be neutralized to meet CWA permitting guidelines
for the Metal Finishing Point Source category. Sludge from this process
may be required to be managed in accordance with the requirements of
RCRA Subtitle C.
B.3.4.3. Health and Safety Issues
OSHA has set PELs and the ACGIH has set TLVs for chemicals in the
Alcoat 5000 process, as listed in Table B-4.
Table B-4. PELs and TLVs for Chemicals in Alcoat 5000
Process
Chemical OSHA PEL ACGIH TLV
5 mg/m3
Sodium Tripolyphosphate None
Hydrofluoric Acid 3 ppm, as F 3 ppm, as F
(Ceiling)
2.5 mg/m3, as F 2.5 mg/m3, as F
Fluoride Salt
2 mg/m3 (Ceiling)
Potassium Hydroxide None
NIOSH: 2 mg/m3
B-14 Potential Alternatives Report
Ventilation is required to maintain airborne contaminants below the PELs
and TLVs. In addition, personal protection, such as goggles, neoprene
rubber gloves, and respirators, is required. No suspected human
carcinogens, genotoxins or neurotoxins are present in the Alcoat 5000
process. However, hydrofluoric acid is an experimental animal teratogen
and appears in the EPA Genetic Toxicology Program.
B.3.4.4. Additional Supporting Literature
? ACGIH, 1995, Industrial Ventilation: A Manual of
Recommended Practice. 22nd ed. Cincinnati, OH.
? ACGIH, 1991, Documentation of the Threshold Limit
Values and Biological Exposure Indices. 6th ed. Vols I-III.
Cincinnati, OH.
? Lewis, Richard J., Sr., 1992, Sax's Dangerous Properties of
Industrial Materials. 8th ed. Vols I-III. Van Nostrand
Reinhold, New York.
? Manard, Jack. Circle-Prosco, Inc. Telephone
Conversation. November 20, 1995.
? MSDS Information Systems Inc., 1996, OHS MSDS on
Disk.
? National Center for Manufacturing Sciences, 1995,
Alternatives to Chromium for Metal Finishing, Ann Arbor,
Michigan.
? NIOSH, 1994, NIOSH Pocket Guide to Chemical Hazards.
U.S. Government Printing Office, Washington, DC.
? Parker, Doug. Circle-Prosco, Inc. Telephone
Conversation. November 22, 1995 and April 3, 1996.
? 40 CFR part 261 et seq.
? 40 CFR part 400 et seq.
? 40 CFR part 129 et seq.
? 42 USC ?412(b)
Point of Contact
General Inquiries: Technical Inquiries:
Jack Manard Doug Parker
Circle-Prosco, Inc. Phone: 812-339-3653
2017 Yost Avenue Fax: 812-331-2566
Bloomington, IN 47403
Phone: 317-579-5353
Fax: 317-579-5354
Potential Alternatives Report B-15
B.4. COBALT-BASED COATINGS
Several cobalt-based coatings are commercially available, but only Alodine 2000
has been historically tested for aerospace applications.
B.4.1. Alodine 2000 (Parker Amchem)
Alodine 2000 is a coating that is currently commercially available from Parker
Amchem specifically designed for aerospace applications. It was originally
developed and patented by Boeing Aircraft Company. The Alodine 2000 process
uses cobalt and molybdenum to treat aluminum surfaces. When using Alodine
2000, the process steps listed below are recommended.
1. Cleaning: Parker Amchem recommends using Ridoline 53.
Ridoline 53 contains sodium metasilicate and tetrasodium
pyrophosphate. This bath is maintained between 140癋 and 160癋.
2. Water Rinsing
3. Deoxidizing: Parker Amchem recommends Deoxidizer 6 with
Replenisher 16. Hydrofluoric acid, chromic acid, magnesium
acetate, and triethanolamine are present during this process step.
The bath is maintained between 50癋 and 90癋.
4. Water Rinsing
5. Conversion Coat with Alodine TD 2000H: Although a complete
list of constituents of Alodine 2000H is not available, regulated
and hazardous chemicals include cobalt nitrate, hydrogen peroxide,
magnesium acetate, and triethanolamine. The conversion coating
bath should be maintained between 120癋 and 140癋.
6. Water rinsing
7. Post-Treatment: A proprietary tungsten/vanadium seal (TD
3095Y) is recommended by Parker Amchem for post-treatment.
This seal enhances both the corrosion resistance and the paint
adhesion of the final coating.
8. Water Rinsing
9. Drying: Drying may be performed with heat or by air drying.
B.4.1.1. Technical Considerations
NCMS issued a study that compared nonchromate conversion coatings to
Alodine 600 and 1200 series coatings (chrome conversion coatings
manufactured by Parker Amchem) on aluminum substrates. Among the
alternatives tested was Alodine 2000. Below is a summary of the findings.
? Corrosion Resistance: Alodine 2000 passed corrosion
resistance tests on aluminum alloy 2024 and alloy 7075,
B-16 Potential Alternatives Report
and exceeded test requirements for alloy 6061. Tests
followed MIL-C-5541 procedures.
? Contact Electrical Resistance: Alodine 2000 passed
contact electrical resistance tests on alloy 6061 before a salt
spray. Tests followed MIL-C-81706 procedures.
Substrates coated with Alodine 2000 were also tested until
failure after a salt spray. The coatings had a mean contact
electrical resistance of 1,620 m/in2.
? Paint Adhesion: Alodine 2000 passed dry and wet paint
adhesion tests on aluminum alloys 2024 and 6061. It
passed the dry paint adhesion test on alloy 7075, but failed
the wet paint adhesion test on this alloy. Tests followed
MIL-C-5541 and MIL-C-81706 procedures.
The MITRE Corporation performed a study to identify alternatives to
chrome conversion coatings for the McClellan Air Force Base. Alodine
2000 was one of the three alternatives studied. The information listed
below was reported.
? Corrosion Resistance: Salt spray testing was performed
with unpainted and painted Alodine 2000 coatings.
Unpainted substrates had a salt spray resistance of over 336
hours (the requirement for MIL-C-81706). In addition,
painted substrates had a salt spray resistance of over 1,500
hours.
? Contact Electrical Resistance: Alodine 2000 had a contact
electrical resistance of over 5 m/in2 before the salt spray,
and under 10 m/in2 after the salt spray.
? Paint Adhesion: Alodine 2000 passed both cross-hatch and
wet tape tests.
To date, parts that have been coated with Alodine 2000 have not required
repair. Brush-up techniques are not available with this coating. However,
Parker Amchem recommends using any repair techniques that are required
by military specifications for chrome conversion coatings. One example is
a ChemFilm Alodine Pen, which contains chromium.
B.4.1.2. Environmental Issues
The Alodine 2000 process contains three chemicals that are regulated as
HAPs under Title III of the CAA. The HAPs are present in the deoxidizer
step (Step 3) and the conversion coating step (Step 5). Due to the acidic
and basic nature of the wastewaters from the Alodine 2000 process, the
wastewaters must be neutralized to meet CWA permitting guidelines for
the Metal Finishing Point Source category. Sludge from this process may
Potential Alternatives Report B-17
be required to be managed in accordance with the requirements of RCRA
Subtitle C.
B.4.1.3. Health and Safety Issues
OSHA has set PELs and the ACGIH has set TLVs for chemicals in the
Alodine 2000 process, as listed in Table B-5.
Table B-5. PELs and TLVs for Chemicals in Alodine 2000 Process
Chemical OSHA PEL ACGIH TLV
Nitric Acid 2 ppm 2 ppm
0.02 mg/m3 as Co
Cobalt Nitrate None
Sodium Ammonium None None
Vanadate NIOSH: 0.05 mg
V/m3/ 15 minutes
Hydrogen Peroxide 1 ppm 1 ppm
5 mg/m3
Triethanolamine None
Table B-6 lists the chemical products of the Alodine 2000 process as well
as the constituent chemicals present during the process.
Table B-6. Chemical Products of Alodine 2000 Process
Product Constituent CAS Percent
Number by
Mass
TD-3072-W N-Octyl 2- 07425-87-8 1-10
Pyrrolidone
Sodium 06834-92-0 1-10
Metasilicate
Surfactants N.A. 10-30
Ridoline 53 LF Surfactants N.A. 1-10
Deoxalume ?2200 Nitric Acid 07697-37-2 10-30
Deoxalume ?2200 Hydrogen 07722-84-1 30-40
Replenisher Peroxide
Surfactant N.A. 1-10
(Table B-6 continued on next page)
B-18 Potential Alternatives Report
Table B-6. Chemical Products of Alodine 2000 Process
(Continued)
Product Constituent CAS Percent
Number by
Mass
PTD 2000H Cobalt Nitrate 10141-05-6 1-10
Magnesium 00142-72-3 10-30
Acetate
Alodine 2600 Toner Hydrogen 07722-84-1 30-40
Peroxide
PTD 2000I Triethanolamine 00102-71-6 10-30
PTD 3095Y Sodium 12055-09-3 N.A.
Ammonium
Vanadate
N.A. = Not Available
Ventilation is required to maintain airborne contaminants below the PELs
and TLVs. In addition, personal protection, such as goggles and
respiratory equipment, is required. Dermal contact with the chemicals can
cause allergic skin reactions. In addition, inhalation of the chemicals in
dust form can cause illness and respiratory disease. Cobalt nitrate and
triethanolamine are suspected human carcinogens. Hydrogen peroxide is a
confirmed human genotoxin. Sodium metasilicate, nitric acid, hydrogen
peroxide, and cobalt nitrate are experimental animal teratogens and/or
reproductive toxicants. No other known or suspected carcinogens,
teratogens, mutagens, or neurotoxins were noted in Alodine 2000.
B.4.1.4. Additional Supporting Literature
? ACGIH, 1995, Industrial Ventilation: A Manual of
Recommended Practice. 22nd ed. Cincinnati, OH.
? ACGIH, 1996, 1996 TLVs and BEIs. Threshold Limit
Values for Chemical Substances and Physical Agents.
Biological Exposure Indices. Second Printing. ACGIH,
Cincinnati, OH.
? Lewis, Richard J., Sr., 1996, Sax's Dangerous Properties of
Industrial Materials. 9th ed. Vols I-III. Van Nostrand
Reinhold, New York.
? MSDS Information Systems Inc., 1996, OHS MSDS on
Disk.
? Meyers, Barry R., MITRE Corporation; Steve C. Lynn,
MITRE Corporation; and Elwin Jang, McClellan Air Force
Potential Alternatives Report B-19
Base. "Case Study - Alternatives to the Use of Chromium
in Plating and Conversion Coating at McClellan Air Force
Base, California." 9th Annual Aerospace Hazardous
Materials Management Conference. Denver, Colorado.
September 28-30, 1994.
? National Center for Manufacturing Sciences, 1995,
Alternatives to Chromium for Metal Finishing, Ann Arbor,
Michigan.
? NIOSH, 1994, NIOSH Pocket Guide to Chemical Hazards.
U.S. Government Printing Office, Washington, DC.
? Nylen, Jon. Parker Amchem. Telephone Conversation.
November 14, 1995 and April 4, 1996.
? Parker Amchem, 1992. Deoxalume?2200 Additive
Material Safety Data Sheet, Parker Amchem, Madison Hts.,
MI.
? Parker Amchem, 1994. PTD-2000-H Material Safety Data
Sheet, Parker Amchem, Madison Hts., MI.
? Parker Amchem, 1994. PTD-2000-I Material Safety Data
Sheet, Parker Amchem, Madison Hts., MI.
? Parker Amchem, 1995. Alodine 2000 Material Safety Data
Sheet, Parker Amchem, Madison Hts., MI.
? Parker Amchem, 1995. Alodine 2600 Toner Material
Safety Data Sheet, Parker Amchem, Madison Hts., MI.
? Parker Amchem, 1995. Deoxalume?2200 Material Safety
Data Sheet, Parker Amchem, Madison Hts., MI.
? Parker Amchem, 1995. PTD-3095-Y Material Safety Data
Sheet, Parker Amchem, Madison Hts., MI.
? Parker Amchem, 1995. Ridoline 53 LF Material Safety
Data Sheet, Parker Amchem, Madison Hts., MI.
? 40 CFR part 261 et seq.
? 40 CFR part 400 et seq.
? 40 CFR part 129 et seq.
? 42 USC ?412(b)
Point of Contact
Jon Nylen
Parker Amchem
32100 Stephenson Highway
Madison Heights, MI 48071
Phone: 810-589-4893
Fax: 810-583-2976
B-20 Potential Alternatives Report
B.5. RARE EARTH METAL SALTS
Several products in development use the technology of rare earth metal salts. One such
product, Ce-Mo 6061, was identified, and is described below.
B.5.1. Ce-Mo 6061 (University of Southern California)
As with other coatings, these materials may be applied by immersion, although the
bath requires heating. Ce-Mo 6061, developed by the University of Southern
California, uses cerium nitrate (Ce(NO2)3) or cerium chloride (CeCl3) as the rare
earth metal. When applying a Ce-Mo 6061 coating, many steps must be followed
to produce an adequate coating. These steps are listed below.
1. Cleaning: Alconox with hexane is recommended for cleaning by
the University of Southern California. Alconox contains alkyl aryl
sulfonates.
2. Water Rinsing
3. Deoxidizing: The University of Southern California recommends
using Diversey 560 for deoxidation.
4. Water Rinsing
5. Removing Copper: Copper must be removed from the part surface.
The University of Southern California recommends using
Deoxidizer 7 with hydrochloric acid. Deoxidizer 7 contains
sodium bifluoride, potassium nitrate, and potassium dichromate.
6. Water Rinsing
7. Desmutting: The University of Southern California recommends
that desmutting be performed with nitric acid that is maintained
between 104癋 and 113癋.
8. Water Rinsing
9. Oxidizing: Part surfaces are oxidized by baking them at 212癋 for
2 days.
10. Surface Modification 1: During this step, parts are immersed in a
bath containing CeCl3 that is maintained at 212癋.
11. Water Rinsing
12. Surface Modification 2: During this step, parts are immersed in a
bath containing Ce(NO2)3. The bath is maintained at 212癋.
13. Water Rinsing
14. Surface Modification 3: For this surface modification, 500 mV is
applied to parts for 2 hours.
15. Water Rinsing
16. Drying
Although Ce-Mo 6061 is not currently marketed by the University of Southern
California, it has the potential to be distributed because it is patented and licensed.
Potential Alternatives Report B-21
B.5.1.1. Technical Considerations
NCMS issued a study that compared nonchromate conversion coatings to
Alodine 600 and 1200 series coatings (chrome conversion coatings
manufactured by Parker Amchem) on aluminum substrates. Among the
alternatives tested was Ce-Mo 6061. Below is a summary of the findings.
? Corrosion Resistance: Ce-Mo 6061 failed corrosion
resistance tests on aluminum alloys 2024, 6061, and 7075.
Tests followed MIL-C-5541 procedures.
? Contact Electrical Resistance: Ce-Mo 6061 passed contact
electrical resistance tests on alloy 6061 before a salt spray.
Tests followed MIL-C-81706 procedures. Substrates
coated with Ce-Mo 6061 were also tested until failure after
a salt spray. The coatings had a mean contact electrical
resistance of 2,180 m/in2.
? Paint Adhesion: Ce-Mo 6061 passed wet paint adhesion
tests on aluminum alloy 6061, but failed dry paint adhesion
tests on that alloy. Results were not available for other
aluminum alloys. Tests followed MIL-C-5541 and MIL-C-
81706 procedures.
This coating has been tested for corrosion resistance after scratching the
coating. Tests were performed by placing the scratched parts in a sodium
chloride solution. The parts did not corrode; therefore, the University of
Southern California believes that touch-up techniques may not be
necessary. If touch-up is necessary, it is expected that cerium nitrate may
be able to be brushed on to repair the coating; however, this has not been
tested.
B.5.1.2. Environmental Issues
The Ce-Mo 6061 process contains four chemicals in the sixteen-step
process that are regulated as HAPs under Title III of the CAA. One HAP
is in the cleaning step, two are in the copper removal step, and one is in the
desmutting step. Wastewater from the acidic process steps, including
copper removal and desmutting, must be neutralized under the CWA. In
addition, hexane, Alconox, chromium compounds, and fluoride
compounds from the process will require further treatment. Sludge from
this process may be required to be managed in accordance with the
requirements of RCRA Subtitle C.
B-22 Potential Alternatives Report
B.5.1.3. Health and Safety Issues
OSHA has set PELs and the ACGIH has set TLVs for chemicals in the Ce-
Mo 6061 process, as listed in Table B-7.
Table B-7. PELs and TLVs for Chemicals in Ce-Mo 6061 Process
Chemical OSHA PEL ACGIH TLV
Hexane n-Hexane: 500 ppm n-Hexane: 50 ppm
Other Isomers: None Other Isomers:
NIOSH: 100 ppm 500 ppm
2.5 mg/m3, as F 2.5 mg/m3, as F
Sodium Bifluoride
0.1 mg/m3, as CrO3 0.05 mg/m3 as Cr
Potassium Dichromate
Hydrochloric Acid 5 ppm 5 ppm
Nitric Acid 2 ppm 2 ppm
Ventilation is required to maintain airborne contaminants below the PELs
and TLVs. In addition, personal protection, such as goggles, face shields,
gloves and respirators, is required. Potassium dichromate, used during
copper removal, is a suspected carcinogen. Nitric acid and hexane are
experimental teratogens. Hexane is a suspected animal genotoxin.
Hexane has demonstrated detrimental effects on the human central
nervous system.
B.5.1.4. Additional Supporting Literature
? ACGIH, 1995, Industrial Ventilation: A Manual of
Recommended Practice. 22nd ed. Cincinnati, OH.
? ACGIH, 1991, Documentation of the Threshold Limit
Values and Biological Exposure Indices. 6th ed. Vols I-III.
Cincinnati, OH.
? Lewis, Richard J., Sr., 1992, Sax's Dangerous Properties of
Industrial Materials. 8th ed. Vols I-III. Van Nostrand
Reinhold, New York.
? Mansfeld, Florian. University of Southern California.
Telephone Conversation. November 20, 1995 and April 9,
1996.
? MSDS Information Systems Inc., 1996, OHS MSDS on
Disk.
? National Center for Manufacturing Sciences, 1995,
Alternatives to Chromium for Metal Finishing, Ann Arbor,
Michigan.
Potential Alternatives Report B-23
? NIOSH, 1994, NIOSH Pocket Guide to Chemical Hazards.
U.S. Government Printing Office, Washington, DC.
? 40 CFR part 261 et seq.
? 40 CFR part 400 et seq.
? 40 CFR part 129 et seq.
? 42 USC ?412(b)
Point of Contact
Florian Mansfeld
University of Southern California
Dept. of Materials Science
Los Angeles, CA 90089-0241
Phone: 213-740-4428
Fax: 213-740-7797
B-24 Potential Alternatives Report
B.6. MANGANESE OXIDE FILMS
Two products were identified that utilize potassium permanganate solutions to create a
manganese oxide coating. Patclin 1910 and Sanchem FP are described below.
B.6.1. Patclin 1910B (Patclin Chemical Company, Inc.)
Patclin 1910B, currently available from Patclin Chemical Company, Inc., is one of
a family of products that utilize potassium permanganates to treat surfaces. The
Patclin 1910B process is described below.
1. Cleaning: Patclin Chemical Company recommends using Patclin
342 for cleaning parts. Patclin 342 contains sodium metasilicate
and sodium tripolyphosphate. The cleaning bath is maintained at
160癋.
2. Water Rinsing
3. Etching: Patclin Chemical Company, Inc. recommends using
Patclin 366G for etching parts to be conversion coated. This
etchant contains sodium hydroxide and sodium gluconate. The
bath is maintained at 140癋.
4. Water Rinsing
5. Desmuttering
6. Water Rinsing
7. Conversion Coating with Patclin 1910B: Patclin 1910B contains
sodium fluoride and potassium permanganate. The bath is
maintained at 170癋.
8. Water Rinsing
9. Drying: After conversion coating and rinsing, coatings are dried
for 40 minutes at 430癋.
B.6.1.1. Technical Considerations
NCMS issued a study that compared nonchromate conversion coatings to
Alodine 600 and 1200 series coatings (chrome conversion coatings
manufactured by Parker Amchem) on aluminum substrates. Among the
alternatives tested was Patclin 1910B. Below is a summary of the
findings.
? Corrosion Resistance: Patclin 1910B failed corrosion
resistance tests on aluminum alloys 2024, 6061, and 7075.
Tests followed MIL-C-5541 procedures.
? Contact Electrical Resistance: Patclin 1910B passed
contact electrical resistance tests on alloy 6061 before a salt
Potential Alternatives Report B-25
spray. Tests followed MIL-C-81706 procedures.
Substrates coated with Patclin 1910B were also tested until
failure after a salt spray. The coatings had a mean contact
electrical resistance of 179 m/in2.
? Paint Adhesion: Patclin 1910B failed wet and dry paint
adhesion tests on alloys 2024, 6061, and 7075. Tests
followed MIL-C-5541 and MIL-C-81706 procedures.
Touch-up techniques for Patclin 1910B have not been identified by Patclin
Chemical Company to date.
B.6.1.2. Environmental Issues
The Patclin 1910B process contains three chemicals that are regulated as
HAPs under Title III of the CAA. One HAP is in Patclin 366G, one is in
the desmuttering step, and one (manganese) is in Patclin 1910B.
Wastewater from all process steps, except for cleaning and water rinsing,
must be neutralized under the CWA. It is unknown if other chemicals in
the wastewater will require further treatment. Although this process
creates very little waste, sludge from the process baths may be considered
to be a listed hazardous waste under RCRA.
B.6.1.3. Health and Safety Issues
OSHA has set PELs and the ACGIH has set TLVs for chemicals in the
Patclin 1910B process, as listed in Table B-8.
Table B-8. PELs and TLVs for Chemicals in Patclin 1910B Process
Chemical OSHA PEL ACGIH TLV
2 mg/m3 (Ceiling) 2 mg/m3 (Ceiling)
Sodium Hydroxide
Nitric Acid 2 ppm 2 ppm
2.5 mg/m3 as F 2.5 mg/m3 as F
Ammonium Bifluoride
2.5 mg/m3 as F 2.5 mg/m3 as F
Sodium Fluoride
5 mg/m3 as Mn 0.2 mg/m3 as Mn
Potassium Permanganate
Ventilation is required to maintain airborne contaminants below the PELs
and TLVs. In addition, personal protection, such as respirators and
goggles, is required. No suspected carcinogens are present during the
Patclin 1910B process. Sodium hydroxide is an experimental animal
genotoxin. Nitric acid and hydrofluoric acid are experimental animal
B-26 Potential Alternatives Report
teratogens. Hydrofluoric acid appears in EPA's Genetic Toxicity
Program.
B.6.1.4. Additional Supporting Literature
? ACGIH, 1995, Industrial Ventilation: A Manual of
Recommended Practice. 22nd ed. Cincinnati, OH.
? ACGIH, 1991, Documentation of the Threshold Limit
Values and Biological Exposure Indices. 6th ed. Vols I-III.
Cincinnati, OH.
? Lewis, Richard J., Sr., 1992, Sax's Dangerous Properties of
Industrial Materials. 8th ed. Vols I-III. Van Nostrand
Reinhold, New York.
? MSDS Information Systems Inc., 1996, OHS MSDS on
Disk.
? National Center for Manufacturing Sciences, 1995,
Alternatives to Chromium for Metal Finishing, Ann Arbor,
Michigan.
? NIOSH, 1994, NIOSH Pocket Guide to Chemical Hazards.
U.S. Government Printing Office, Washington, DC.
? Reinecke, Ray. Patclin Chemical Company, Inc.
Telephone Conversation. November 20, 1995 and April 4,
1996.
? 40 CFR part 261 et seq.
? 40 CFR part 400 et seq.
? 40 CFR part 129 et seq.
? 42 USC ?412(b)
Point of Contact
Ray Reinecke or Rubin Operosky
Patclin Chemical Company, Inc.
66 Alexander Street
Yonkers, NY 10701
Phone: 914-476-7000
Fax: 914-476-0934
B.6.2. Sanchem FP (Sanchem)
Two processes that use potassium permanganate are the Sanchem FP (Full
Process) and the Sanchem SD (Single Dip). Commercially, Sanchem SD has
widespread use. Sanchem FP currently is being used by one facility. Only
Sanchem FP is discussed in this document because it meets the selection criteria
Potential Alternatives Report B-27
as an alternative to chrome conversion coating. The Sanchem FP process is
described below.
1. Cleaning
2. Water Rinsing
3. Deoxidizing
4. Water Rinsing
5. Forming Initial Oxide Film: Parts may be placed in boiling de-
ionized (DI) water to form an initial oxide film. An alternative to
using boiling DI water is using 230癋 steam.
6. Safeguard 2000: Safeguard 2000 consists of aluminum nitrate and
lithium nitrate. This chemical is maintained at 190癋 to 200癋.
This can be an immersion or spray process, and parts are immersed
or sprayed for 2 minutes. In actuality, this step forms a light
"anodize" coating.
7. Water Rinsing
8. Safeguard 3000: A potassium permanganate solution, Safeguard
3000, is used to increase the oxide thickness after conversion
coating. In addition, it deposits a manganese oxide layer that
provides corrosion resistance. The solution is maintained at 140癋
to 150癋, and parts are immersed for 3 minutes.
9. Water Rinsing
10. Sealing: After conversion coating, parts are placed in a hot
potassium silicate solution to seal the oxide film.
11. Water Rinsing
12. Drying
B.6.2.1. Technical Considerations
NCMS issued a study that compared nonchromate conversion coatings to
Alodine 600 and 1200 series coatings (chrome conversion coatings
manufactured by Parker Amchem) on aluminum substrates. Among the
alternatives tested was Sanchem FP. Below is a summary of the findings.
? Corrosion Resistance: Sanchem FP failed corrosion
resistance tests on aluminum alloys 2024, 6061, and 7075.
Tests followed MIL-C-5541 procedures.
? Contact Electrical Resistance: Sanchem FP passed contact
electrical resistance tests on alloy 6061 before a salt spray.
Tests followed MIL-C-81706 procedures. Substrates
coated with Sanchem FP were also tested until failure after
a salt spray. The coatings had a mean contact electrical
resistance of 471 m/in2.
B-28 Potential Alternatives Report
? Paint Adhesion: Sanchem FP passed dry and wet paint
adhesion tests on alloy 7075. It passed the dry paint
adhesion test on alloy 2024, but failed the wet paint
adhesion test on that alloy. It passed the wet paint adhesion
test on alloy 6061, but failed the dry paint adhesion test.
Tests followed MIL-C-5541 and MIL-C-81706 procedures.
The MITRE Corporation performed a study (MITRE, 1994) to identify
alternatives to chrome conversion coatings for the McClellan Air Force
Base. Safeguard CC, which is a generic Sanchem FP process, was one of
the three alternatives discussed in the document. The information listed
below was reported.
? Corrosion Resistance: Salt spray testing was performed
with unpainted and painted Safeguard CC coatings.
Unpainted substrates had a salt spray resistance of over 168
hours (the requirement for MIL-C-5541). In addition,
painted substrates had a salt spray resistance of over 2,000
hours.
? Contact Electrical Resistance: Safeguard CC had a contact
electrical resistance of over 5 m/in2 before the salt spray,
and over 10 m/in2 after the salt spray.
? Paint Adhesion: Safeguard CC passed both cross-hatch
and wet tape tests.
If this coating becomes scratched or marred, a substance such as Safeguard
6000, which is available from Sanchem, may be used to repair the coating.
Safeguard 6000 is based on potassium permanganate and acetic acid.
Safeguard 6000 is currently being tested by Alcan Aluminum in England
and by Lockheed in the United States. It may be used to repair a wide
variety of aluminum substrates.
Although Sanchem FP is a potential alternative, it is slower than the
chrome conversion process. For example, the immersion process takes 30
minutes minimum, while the chrome conversion coating process takes 3 to
5 minutes.
B.6.2.2. Environmental Issues
The Sanchem process contains at least one chemical that is regulated as a
HAP under Title III of the CAA. Specifically, the manganese that is in the
potassium permanganate is regulated as a HAP. Under the CWA,
wastewater from the process may require neutralization. Compounds may
also be present in Sanchem FP that require further treatment. Sludge from
Potential Alternatives Report B-29
this process may be required to be managed in accordance with the
requirements of RCRA Subtitle C.
B.6.2.3. Health and Safety Issues
OSHA has set PELs and the ACGIH has set TLVs for chemicals in the
Sanchem FP process, as listed in Table B-9.
Table B-9. PELs and TLVs for Chemicals in Sanchem FP Process
Chemical OSHA PEL ACGIH TLV
15 mg/m3 Total 10 mg/m3
Powder
3
5 mg/m Respirable
2 mg/m3 Al
Aluminum Nitrate None
NIOSH: 2 mg/m3 Al
5 mg/m3 as Mn 0.2 mg/m3 as Mn
Potassium Permanganate
Table B-10 lists the chemical products of the Sanchem FP process as well
as the constituent chemicals present during the process.
Table B-10. Chemical Products of Sanchem FP Process
Product Constituent CAS Percent
Number by
Mass
Sanchem 500 White Powder N.A. N.A.
Sanchem CC-1000 Sodium Bromate 07789-38-0 N.A.
Safeguard 2000 Aluminum 13473-90-0 N.A.
Nitrate
Lithium Nitrate N.A. N.A.
Safeguard 3000 Potassium 07722-64-7 N.A.
Permanganate
Safeguard 4000 N.A. N.A. N.A.
N.A. = Not Available
Ventilation is required to maintain airborne contaminants below the PELs
and TLVs. In addition, personal protection, such as respirators and
goggles, may be required. Mutation data exists for potassium
permanganate and it is also an experimental animal teratogen/reproductive
toxicant. No other known or suspected carcinogens, teratogens, mutagens,
or neurotoxins were noted in Sanchem FP.
B-30 Potential Alternatives Report
B.6.2.4. Additional Supporting Literature
? ACGIH, 1995, Industrial Ventilation: A Manual of
Recommended Practice. 22nd ed. Cincinnati, OH.
? ACGIH, 1996, 1996 TLVs and BEIs. Threshold Limit
Values for Chemical Substances and Physical Agents.
Biological Exposure Indices. Second Printing. ACGIH,
Cincinnati, OH.
? Bibber. Sanchem. Telephone Conversation. November
21, 1995 and April 4, 1996.
? Flicher, Jon. Sanchem. Telephone Conversation.
November 21, 1995.
? Lewis, Richard J., Sr., 1996, Sax's Dangerous Properties of
Industrial Materials. 9th ed. Vols I-III. Van Nostrand
Reinhold, New York.
? MSDS Information Systems Inc., 1996, OHS MSDS on
Disk.
? Meyers, Barry R., MITRE Corporation; Steve C. Lynn,
MITRE Corporation; and Elwin Jang, McClellan Air Force
Base. "Case Study - Alternatives to the Use of Chromium
in Plating and Conversion Coating at McClellan Air Force
Base, California." 9th Annual Aerospace Hazardous
Materials Management Conference. Denver, Colorado.
September 28-30, 1994.
? National Center for Manufacturing Sciences, 1995,
Alternatives to Chromium for Metal Finishing, Ann Arbor,
Michigan.
? NIOSH, 1994, NIOSH Pocket Guide to Chemical Hazards.
U.S. Government Printing Office, Washington, DC.
? Sanchem, 1990. Sanchem 500 Material Safety Data Sheet,
Sanchem, Chicago, IL.
? Sanchem, 1990. Sanchem CC-1000 Material Safety Data
Sheet, Sanchem, Chicago, IL.
? Sanchem, 1994. Safeguard 2000 Material Safety Data
Sheet, Sanchem, Chicago, IL.
? Sanchem, 1994. Safeguard CC-3000 Material Safety Data
Sheet, Sanchem, Chicago, IL.
? 40 CFR part 261 et seq.
? 40 CFR part 400 et seq.
? 40 CFR part 129 et seq.
? 42 USC ?412(b)
Potential Alternatives Report B-31
Point of Contact
Dr. Bibber
Sanchem
1600 South Canal Street
Chicago, IL 60616
Phone: 312-733-6100
Fax: 312-733-7432
B-32 Potential Alternatives Report
B.7. FLUOTITANIC COATINGS
One product using fluotitanic coating technology, Permatreat 611, was identified as a
promising alternative to chrome conversion coatings in aerospace applications.
B.7.1. Permatreat 611 (Betz Laboratories)
Permatreat 611, distributed by Betz Laboratories, is a possible alternative to
chrome conversion coatings. Although Permatreat 611 has been widely used in a
variety of applications, it has not been used in the aerospace industry to date. It
requires only four steps, as listed below.
1. Cleaning: Betz Laboratories recommends using Betz Kleen 156
and Betz Sol 104 for cleaning parts. Betz Kleen 156 contains
sodium hydroxide, while Betz Sol 104 contains alcohols and
alkylated fatty alcohol. This bath is at ambient temperature.
2. Water Rinsing
3. Conversion Coating with Permatreat 611: Permatreat 611
contains fluotitanic acid and a proprietary, low-volatility organic
polymer. It is a dry, in-place treatment in which the chemicals are
applied to the part surface, and the chemicals are allowed to drain
off. The chemicals are maintained at ambient temperature.
4. Drying
B.7.1.1. Technical Considerations
NCMS issued a study that compared nonchromate conversion coatings to
Alodine 600 and 1200 series coatings (chrome conversion coatings
manufactured by Parker Amchem) on aluminum substrates. Among the
alternatives tested was Permatreat 611. Below is a summary of the
findings.
? Corrosion Resistance: Permatreat 611 failed corrosion
resistance tests on aluminum alloys 2024, 6061, and 7075.
Tests followed MIL-C-5541 procedures.
? Contact Electrical Resistance: Permatreat 611 passed
contact electrical resistance tests on alloy 6061 before a salt
spray. Tests followed MIL-C-81706 procedures.
Substrates coated with Permatreat 611 were also tested
until failure after a salt spray. The coatings had a mean
contact electrical resistance of 480 m/in2.
? Paint Adhesion: Permatreat 611 passed dry and wet paint
adhesion tests on alloys 2024 and 7075. It also passed the
Potential Alternatives Report B-33
wet paint adhesion test on alloy 6061, but failed the dry
paint adhesion test on that alloy. Tests followed MIL-C-
5541 and MIL-C-81706 procedures.
Scratches in the coating can be repaired by brushing on the original
solution type (typically 1.5%) of Permatreat 611. After brushing on the
solution, the part needs to dry thoroughly before using it again.
B.7.1.2. Environmental Issues
The Permatreat 611 process, specifically the cleaning step, contains one
chemical that is regulated as a HAP under Title III of the CAA. Under the
CWA, wastewater from the process must be neutralized. Compounds may
also be present in Permatreat 611 that require further treatment. Sludge
from this process may be required to be managed in accordance with the
requirements of RCRA Subtitle C.
B.7.1.3. Health and Safety Issues
OSHA has set PELs and the ACGIH has set TLVs for chemicals in the
Permatreat 611 process, as listed in Table B-11.
Table B-11. PELs and TVLs for Chemicals in Permatreat 611 Process
Chemical OSHA PEL ACGIH TLV
2 mg/m3 (Ceiling) 2 mg/m3 (Ceiling)
Sodium Hydroxide
2.5 mg/m3 as F 2.5 mg/m3 as F
Fluotitanic Acid
Ventilation is required to maintain airborne contaminants below the PELs
and TLVs. In addition, personal protection, such as respirators and
goggles, is required. Permatreat 611 may cause lung damage if respirators
are not used. No suspected carcinogens are present during the Permatreat
611 process. However, sodium hydroxide is an experimental animal
genotoxin.
B.7.1.4. Additional Supporting Literature
? ACGIH, 1995, Industrial Ventilation: A Manual of
Recommended Practice. 22nd ed. Cincinnati, OH.
? ACGIH, 1991, Documentation of the Threshold Limit
Values and Biological Exposure Indices. 6th ed. Vols I-III.
Cincinnati, OH.
B-34 Potential Alternatives Report
? Kasouff, Mitch. Betz Laboratories, Inc. Telephone
Conversation. November 20, 1995 and April 4, 1996.
? Lewis, Richard J., Sr., 1992, Sax's Dangerous Properties of
Industrial Materials. 8th ed. Vols I-III. Van Nostrand
Reinhold, New York.
? MSDS Information Systems Inc., 1996, OHS MSDS on
Disk.
? National Center for Manufacturing Sciences, 1995,
Alternatives to Chromium for Metal Finishing, Ann Arbor,
Michigan.
? NIOSH, 1994, NIOSH Pocket Guide to Chemical Hazards.
U.S. Government Printing Office, Washington, DC.
? 40 CFR part 261 et seq.
? 40 CFR part 400 et seq.
? 40 CFR part 129 et seq.
? 42 USC ?412(b)
Point of Contact
Mitch Kasouff
Betz Laboratories, Inc.
Betz Metchem Division
200A Precision Drive
Horsham, PA 19044
Phone: 215-773-2822
Fax: 215-773-2800
Potential Alternatives Report B-35
B.8. TALC COATINGS
Sandia National Labs has developed several talc coatings that may be considered
alternatives to chrome conversion coatings. Two of these coatings are described below.
B.8.1. Sandia 1 and Sandia 2 (Sandia National Laboratories)
Sandia 1 and Sandia 2 are two talc coatings. The main difference between these
alternatives is the treatment time. The Sandia 1 and Sandia 2 process steps are
listed below.
1. Cleaning: Sandia National Laboratories recommends Alconox,
which contains alkyl aryl sulfonates.
2. Water Rinsing
3. Alkaline Degreasing: Sodium metasilicate and sodium carbonate
are recommended by Sandia National Laboratories for alkaline
degreasing. This bath is maintained at 149癋.
4. Water Rinsing
5. Etching: Sandia National Laboratories recommends using
Sanchem 1000 for etching prior to conversion coating. Sanchem
1000, which is maintained at 122癋, contains sodium bromate and
nitric acid.
6. Water Rinsing
7. Conversion Coating with Sandia 1 or Sandia 2: Sandia 1 and
Sandia 2 contain sodium aluminate and lithium carbonate.
Processing time for Sandia 1 is 15 minutes, and for Sandia 2 is
5 hours. The process is maintained at 131癋.
8. Water Rinsing
9. Drying
Sandia 1 and Sandia 2 are not commercially available to date.
B.8.1.1. Technical Considerations
NCMS issued a study that compared nonchromate conversion coatings to
Alodine coatings (chrome conversion coatings manufactured by Parker
Amchem) on aluminum substrates. Sandia 1 and Sandia 2 were tested as
alternatives to chrome conversion coatings. Below is a summary of the
findings.
B-36 Potential Alternatives Report
Sandia 1
? Corrosion Resistance: Sandia 1 coatings failed corrosion
resistance tests on aluminum alloys 2024, 6061, and 7075.
Tests followed MIL-C-5541 procedures.
? Contact Electrical Resistance: Sandia 1 coatings passed
contact electrical resistance tests on alloy 6061 before a salt
spray. Tests followed MIL-C-81706 procedures.
Substrates coated with Sandia 1 were also tested until
failure after a salt spray. The coatings had a mean contact
electrical resistance of 397 m/in2.
? Paint Adhesion: Sandia 1 failed dry and wet paint adhesion
tests on alloys 2024, 6061, and 7075. Tests followed MIL-
C-5541 and MIL-C-81706 procedures.
Sandia 2
? Corrosion Resistance: Sandia 2 coatings passed corrosion
resistance tests on aluminum alloy 6061. However, they did
not pass tests on alloy 2024 or alloy 7075. Tests followed
MIL-C-5541 procedures.
? Contact Electrical Resistance: Sandia 2 coatings failed
contact electrical resistance tests on alloy 6061 before a salt
spray. Tests followed MIL-C-81706 performance
requirements. Substrates coated with Sandia 2 were also
tested until failure after a salt spray. The coatings had a
mean contact electrical resistance of 23,700 m/in2.
? Paint Adhesion: Sandia 2 failed dry and wet paint adhesion
tests on alloys 2024, 6061, and 7075. Tests followed MIL-
C-5541 and MIL-C-81706 procedures.
Sandia 1 and Sandia 2 have been evaluated for touch-up techniques.
Brushing on the original solution was successful for repair of the coating.
B.8.1.2. Environmental Issues
Ozone-depleting substances (ODSs) and HAPs are not present in Sandia 1
or Sandia 2. Neutralization is not required for any of the wastewater, but
the cleaning wastewater must be treated to remove Alconox. Sludge from
the process baths may be considered to be a listed hazardous waste under
RCRA.
Potential Alternatives Report B-37
B.8.1.3. Health and Safety Issues
Personal protection such as goggles and rubber gloves must be utilized.
Respirators may be required, depending on the airborne concentration of
the lithium carbonate. Carcinogens are not present in Sandia 1 or Sandia
2, and no OSHA PELs or ACGIH TLVs are applicable to the process.
However, lithium carbonate is a suspected human carcinogen and a human
teratogen and genotoxin. It should be noted that human mutation data has
been reported, and lithium carbonate is a human teratogen by ingestion.
B.8.1.4. Additional Supporting Literature
? ACGIH, 1995, Industrial Ventilation: A Manual of
Recommended Practice. 22nd ed. Cincinnati, OH.
? ACGIH, 1991, Documentation of the Threshold Limit
Values and Biological Exposure Indices. 6th ed. Vols I-III.
Cincinnati, OH.
? Buchheit, Rudy. Sandia National Laboratories. Telephone
Conversation. November 27, 1995 and April 9, 1996.
? Lewis, Richard J., Sr., 1992, Sax's Dangerous Properties of
Industrial Materials. 8th ed. Vols I-III. Van Nostrand
Reinhold, New York.
? MSDS Information Systems Inc., 1996, OHS MSDS on
Disk.
? National Center for Manufacturing Sciences, 1995,
Alternatives to Chromium for Metal Finishing, Ann Arbor,
Michigan.
? NIOSH, 1994, NIOSH Pocket Guide to Chemical Hazards.
U.S. Government Printing Office, Washington, DC.
? 40 CFR part 261 et seq.
? 40 CFR part 400 et seq.
? 40 CFR part 129 et seq.
? 42 USC ?412(b)
Point of Contact
Rudy Buchheit
Sandia National Laboratories
MS 0340, P.O. Box 5800
Albuquerque, NM 87185
Phone: 505-844-6904
Fax: 505-844-1543
B-38 Potential Alternatives Report
B.9. ANODIZING
Anodizing is not a new technology, but there have been some recent developments, and
in many applications, anodizing can replace conversion coatings. One alternative product
and one alternative sealer are described below.
B.9.1. Sulfuric-Boric Acid Anodizing (Boeing Aerospace Corporation)
Anodizing is a process that produces a tough, adherent surface layer by converting
a metal surface to an oxide layer. Sulfuric-boric acid anodizing (SBAA) is one
alternative to chrome conversion coating and is often preferred over other
alternatives, since it provides good corrosion resistance and paint adhesion.
SBAA was originally developed by Boeing Aerospace Corporation to replace
chromic acid anodizing; however, it may also be used to replace chrome
conversion coatings. To apply SBAA, the process steps listed below are typically
followed.
1. Cleaning: Alkaline and/or solvent cleaning must be performed
before anodizing.
2. Water Rinsing
3. Deoxidizing: Deoxidizing can be performed with a variety of
nonchrome deoxidizers.
4. Water Rinsing
5. Sulfuric-Boric Acid Anodizing: After parts are prepared, they are
dipped into a heated bath of sulfuric acid and boric acid.
6. Water Rinsing
7. Sealing: After anodizing, parts are sealed with hot water that
contains 300 ppm chrome, such as magnesium chrome.
This process is patented; however, it is not currently licensed to any specific
company for production.
B.9.1.1. Technical Considerations
The MITRE Corporation performed a study to identify alternatives to
chrome conversion coatings for the McClellan Air Force Base. SBAA
was one of the three alternatives evaluated. The information listed below
was reported.
? Corrosion Resistance: Salt spray testing was performed
with unpainted and painted SBAA coatings on 2024 and
7075 aluminum. Unpainted substrates had a salt spray
resistance of over 336 hours (the requirement for MIL-C-
Potential Alternatives Report B-39
81706). In addition, painted substrates had a salt spray
resistance of over 2,000 hours.
? Contact Electrical Resistance: On 6061 aluminum, SBAA
had a contact electrical resistance of over 5 m/in2 before
the salt spray, and over 10 m/in2 after the salt spray.
? Paint Adhesion: SBAA passed both cross-hatch and wet
tape tests on 2024 and 7075 aluminum alloys.
Similar tests were performed at the Naval Air Warfare Center
(Westminster, Pennsylvania). The results are listed below.
? Corrosion Resistance: Corrosion resistance tests were
performed for 336 hours, according to ASTM B-117
procedures. No surface corrosion occurred on panels
coated with SBAA.
? Paint Adhesion: SBAA coatings passed wet tape paint
adhesion tests. Panels were tested after 24, 96, and 168
hours, and no peeling or removal was identified on the
panels.
If a part needs to be repaired, either Alodine (which contains chromium) or
brush anodizing may be used. One disadvantage of anodizing processes is
that they cannot be used for substrates that have sharp edges or geometries
that can entrap the corrosive fluids.
B.9.1.2. Environmental Issues
The SBAA process contains compounds, specifically chromium and
chromium compounds, that are regulated as HAPs under Title III of the
CAA. Other HAPs may also be present in the cleaners and deoxidizers,
depending on the type chosen. Under the CWA, wastewater from the
process must be neutralized. In addition, metals that are present in the
wastewater from several of the steps, including sealing, will require further
treatment for removal. Sludge from this process may be required to be
managed in accordance with the requirements of RCRA Subtitle C.
B.9.1.3. Health and Safety Issues
OSHA has set PELs and the ACGIH has set TLVs for chemicals in the
SBAA process, as listed in Table B-12.
B-40 Potential Alternatives Report
Table B-12. PELs and TVLs for Chemicals in SBAA Process
Chemical OSHA PEL ACGIH TLV
1 mg/m3 1 mg/m3
Sulfuric Acid
1 mg/m3 0.5 mg/m3as Cr,
Chromium Metals and Insoluble Salts
Cr Metal and Cr
(III) Compounds
0.01 mg/m3,
Insoluble Cr (VI)
Compounds
0.5 mg/m3as 0.5 mg/m3as Cr
Trivalent Chromium
Cr
Other PELs and TLVs may be applicable, depending on the specific
cleaners and deoxidizers used. Ventilation is required to maintain airborne
contaminants below the PELs and TLVs. In addition, personal protection,
such as respirators and goggles, may be required. Sulfuric acid and
chromium compounds are suspected carcinogens. No teratogens,
genotoxins, or neurotoxins are present in this alternative. Sulfuric acid is
an experimental animal teratogen.
B.9.1.4. Additional Supporting Literature
? ACGIH, 1995, Industrial Ventilation: A Manual of
Recommended Practice. 22nd ed. Cincinnati, OH.
? ACGIH, 1991, Documentation of the Threshold Limit
Values and Biological Exposure Indices. 6th ed. Vols I-III.
Cincinnati, OH.
? Groshart, Earl. Boeing Defense and Space Group.
Telephone Conversation. November 22, 1995 and April 4,
1996.
? Lewis, Richard J., Sr., 1992, Sax's Dangerous Properties of
Industrial Materials. 8th ed. Vols I-III. Van Nostrand
Reinhold, New York.
? MSDS Information Systems Inc., 1996, OHS MSDS on
Disk.
? Meyers, Barry R., MITRE Corporation; Steve C. Lynn,
MITRE Corporation; and Elwin Jang, McClellan Air Force
Base. "Case Study - Alternatives to the Use of Chromium
in Plating and Conversion Coating at McClellan Air Force
Base, California." 9th Annual Aerospace Hazardous
Potential Alternatives Report B-41
Materials Management Conference. Denver, Colorado.
September 28-30, 1994.
? National Center for Manufacturing Sciences, (NCMS),
1995, Alternatives to Chromium for Metal Finishing, Ann
Arbor, Michigan.
? NIOSH, 1994, NIOSH Pocket Guide to Chemical Hazards.
U.S. Government Printing Office, Washington, DC.
? Spadafora, Stephen J., Naval Air Warfare Center; and
Frank R. Pepe, NAVMAR Applied Sciences Inc. "A
Comparison of Sulfuric-Boric Acid Anodize and Chromic
Acid Anodize Processes." Metal Finishing. April 1994.
pp. 53-57.
? 40 CFR part 261 et seq.
? 40 CFR part 400 et seq.
? 40 CFR part 129 et seq.
? 42 USC ?412(b)
Point of Contact
Technical: Licensing:
Joe Osborne Bob Ames
Boeing Defense and Space Group Boeing, Corporate
Box 3999 Phone: 425-865-6950
M/S 82-32
Seattle, WA 98124-2499
Phone: 425-865-6950
B.9.2. Alumitec (Alumitec Products Corporation)
Alumitec Products Corporation currently markets a line of products referred to as
Alumitec AC, D, E, FC, and I. These materials contain long-chain carboxylic
acids to treat anodized aluminum parts. The types of Alumitec products are
varied to fit specific applications, as listed bleow.
? Alumitec AC: This is an aircraft grade. It is specifically
formulated for long bath life.
? Alumitec D: This is a standard grade. It consists of 99.9%
isostearic acid and 0.1% benzotriazole.
? Alumitec E: This is a water emulsion for application over oily or
dyed surfaces.
? Alumitec FC: This is acceptable for incidental food contact
because it contains citric acid as a chelating agent.
? Alumitec I: This is acceptable when bath life is not a factor.
B-42 Potential Alternatives Report
This product may be considered more of a sealant for anodizing than a conversion
coating, but it is still included in this document for completeness. The vendor
suggests that this chemical eliminates the need for a conversion coating. The
process consists of the steps listed below.
1. Cleaning: If necessary, parts may be cleaned to remove excess
contaminants.
2. Water Rinsing and Drying: If parts are cleaned, rinsing and drying
may be necessary.
3. Anodizing: Only anodized aluminum parts can be treated with
Alumitec products. Sulfuric acid anodizing may be performed, or
sulfuric/oxalic acid anodizing may be performed for a harder
coating. Sulfuric acid anodizing is performed at 70癋, and
sulfuric/oxalic acid anodizing is performed at 35癋.
4. Water Rinsing and Drying
5. Treatment with Alumitec Product: Parts may be dipped, sprayed,
or wiped with Alumitec products.
6. Tumbling Absorbents or Immersing in NMP: Isostearic acid can
leave an oily residue on part surfaces. Oil may be removed by
tumbling the parts with absorbents or dipping the parts in an
aqueous n-methyl pyrrolidone (NMP) solution.
7. Ambient Air Drying
B.9.2.1. Technical Considerations
Alumitec Products Corporation reports the qualities of their coatings as
listed below.
? Corrosion Resistance: Alumitec Products Corporation has
tested Alumitec products by using ASTM B-117, and
claims that they have between 816 and 1,650 hours
corrosion resistance before getting five pits on aluminum
alloy 2024. Therefore, these products pass corrosion
resistance tests for MIL-C-5541.
? Contact Electrical Resistance: The only information
concerning electrical resistance is that the coating has a
electrical impedance spectroscopy reading of
26 to 27 m/cm2 (approximately 174 m/in2)
? Paint Adhesion: After treatment with NMP, parts were
tested for paint adhesion with epoxy primer and paint. The
requirement was that the salt spray should not drop below
336 hours. If parts were sealed using a 10%, 15%, or 25%
isostearic solution, they took 300, 500, and 1,400 hours,
Potential Alternatives Report B-43
respectively, for failure. Salt spray tests were in accordance
with ASTM B-117. Douglas Aircraft Company conducted
the paintability studies.
This coating is actually a sealer to be used with anodized parts, and is not
used independent of the anodize process. Sulfuric-Boric Acid Anodize
could use these sealants. This alternative has not been tested as
extensively as the others. This sealant is listed for completeness of
identifying alternatives, but by itself, will not be considered a viable
conversion coating alternative.
Although brush plating has not been successful for repair, Alumitec
believes that brush anodizing will be a possible touch-up technique for
scratched parts that were previously coated with Alumitec. After brush
anodizing with a material such as sulfuric acid, the excess sealant should
be wiped off of the part.
B.9.2.2. Environmental Issues
Benzotriazole, isostearic acid, and NMP are not listed as hazardous air
pollutants, and are not considered to be ozone depleting substances. In
addition, the chemicals are not listed as hazardous substances in the CWA,
and are not on the CWA Priority Pollutant list. However, general
requirements for the CAA, CWA, and RCRA may be applicable to this
process.
B.9.2.3. Health and Safety Issues
Benzotriazole, isostearic acid, and NMP and are not regulated by OSHA or
the ACGIH. Alumitec products have a reported LD50 of 25 g/kg.
Benzotriazole was found to be an experimental animal genotoxin, and
NMP was found to be an experimental teratogen. The available MSDS for
NMP presents human neurotoxin concerns.
B.9.2.4. Additional Supporting Literature
? ACGIH, 1995, Industrial Ventilation: A Manual of
Recommended Practice. 22nd ed. Cincinnati, OH.
? ACGIH, 1991, Documentation of the Threshold Limit
Values and Biological Exposure Indices. 6th ed. Vols I-III.
Cincinnati, OH.
B-44 Potential Alternatives Report
? Lewis, Richard J., Sr., 1992, Sax's Dangerous Properties of
Industrial Materials. 8th ed. Vols I-III. Van Nostrand
Reinhold, New York.
? MSDS Information Systems Inc., 1996, OHS MSDS on
Disk.
? National Center for Manufacturing Sciences, 1995,
Alternatives to Chromium for Metal Finishing, Ann Arbor,
Michigan.
? NIOSH, 1994, NIOSH Pocket Guide to Chemical Hazards.
U.S. Government Printing Office, Washington, DC.
? Shulman, Garson P. and A. J. Bauman. Alumitec Products
Corporation. "Organic Sealants for Anodized Aluminum -
Chrome Free Corrosion Protection." 2nd Annual
Techniques for Replacing Chromium: An Information
Exchange. Champion, Pennsylvania. November 7-8, 1995.
? Shulman, Garson. Alumitec Products Corporation.
Telephone Conversation. November 20, 1995 and
April 4, 1996.
? 40 CFR part 261 et seq.
? 40 CFR part 400 et seq.
? 40 CFR part 129 et seq.
? 42 USC ?412(b)
Point of Contact
Garson "Gus" Shulman
Alumitec Products Corporation
3820 Del Amo Blvd. #207
Torrance, CA 90503
Phone: 310-793-9861
Fax: 310-373-2389
Potential Alternatives Report B-45
B.10. PROPRIETARY TECHNIQUES
Six proprietary techniques for replacing chrome conversion coatings were identified by
the technology survey. These products and/or processes are commercially available for
general use, and are therefore possible alternatives to chrome conversion coatings.
B.10.1. Alumicoat 6788 (Elf Atochem - Turco Products Division)
Alumicoat 6788 is a proprietary conversion coating that requires the process steps
listed below.
1. Cleaning
2. Water Rinsing
3. Deoxidizing
4. Water Rinsing
5. Conversion Coating with Alumicoat 6788: This is a nonorganic
bath that contains acrylic and corrosion inhibitors. (It has been
compared to a floor polish.) The conversion coating bath is held at
ambient temperature.
6. Drying: Parts may be allowed to drip dry.
7. Curing: After parts are drip dried, they are cured in an oven for
30 minutes at 180癋.
Alumicoat 6788 is now commercially available from the Turco Products Division
of Elf Atochem. It has been tested by Northrop and Boeing. However, it has not
been purchased and used regularly in an industrial environment.
B.10.1.1. Technical Considerations
NCMS issued a study that compared nonchromate conversion coatings to
Alodine 600 and 1200 series coatings (chrome conversion coatings
manufactured by Parker Amchem) on aluminum substrates. One
alternative tested was referred to as Alumicoat 6788. Below is a summary
of the findings:
? Corrosion Resistance: Alumicoat 6788 coatings exceeded
performance requirements for corrosion resistance tests on
aluminum alloys 2024, 6061, and 7075. Tests followed
MIL-C-5541 procedures.
? Contact Electrical Resistance: Alumicoat 6788 coatings
failed contact electrical resistance tests on alloy 6061
before a salt spray. Tests followed MIL-C-81706
procedures. Substrates coated with Alumicoat 6788 were
also tested until failure after a salt spray. The coatings had
a mean contact electrical resistance of 6,150,000 m/in2.
B-46 Potential Alternatives Report
? Paint Adhesion: Alumicoat 6788 passed dry and wet paint
adhesion tests on aluminum alloys 2024, 6061, and 7075.
Tests followed MIL-C-5541 and MIL-C-81706 procedures.
Elf Atochem expects that scratched parts previously treated with
Alumicoat 6788 may be repaired by simply brushing on Alumicoat 6788
solution over the desired area. However, this touch-up technique has not
been tested.
B.10.1.2. Environmental Issues
Although the constituents of this conversion coating process are proprietary,
the mixture contains no ODSs or HAPs. It is unknown if HAPs are present
during the cleaning, deoxidizing, or conversion coating steps. It is also
unknown if wastewater from the process requires neutralization or further
treatment. Sludge from this process may be required to be managed in
accordance with the requirements of RCRA Subtitle C.
B.10.1.3. Health and Safety Issues
Worker exposure limits have been set for 2-propanol, which is one of the
chemicals in the Alumicoat 6788 process. OSHA has set a PEL of 400
ppm for this chemical, and ACGIH has set a TLV of 400 ppm, as well.
Table B-13 lists the chemical products of the Alumicoat 6788 process as
well as the constituent chemicals present during the process.
Table B-13. Chemical Products of Alumicoat 6788
Process
Product Constituent CAS Percent
Number by
Mass
Alumicoat 6788 N-Methyl 00872-50-4 5
Pyrrolidone
2-Propanol 00067-63-0 <5
Although the constituents of this conversion coating process are
proprietary, the mixture contains no suspected carcinogens. Turco
recommends the use of gloves, respirators, rubber aprons, and goggles for
personnel working with the cleaning and deoxidizing agents. Isopropyl
alcohol is a suspected human carcinogen and a known human neurotoxin.
N-methyl 2-pyrrolidone and isopropanol have been shown to be
experimental animal teratogens and genotoxins. N-methyl pyrrolidone may
Potential Alternatives Report B-47
have deleterious effects on the CNS. The likelihood of the agent
containing other teratogens, genotoxins or neurotoxins is unknown.
B.10.1.4. Additional Supporting Literature
? ACGIH, 1995, Industrial Ventilation: A Manual of
Recommended Practice. 22nd ed. Cincinnati, OH.
? ACGIH, 1996, 1996 TLVs and BEIs. Threshold Limit
Values for Chemical Substances and Physical Agents.
Biological Exposure Indices. Second Printing. ACGIH,
Cincinnati, OH.
? Elf Atochem - Turco Products Division, 1995. Alumicoat
6788 Material Safety Data Sheet, Elf Atochem - Turco
Products Division, Westminster, CA.
? Grainger, John. Elf Atochem. Turco Products Division.
Telephone Conversation. April 10, 1996.
? Lewis, Richard J., Sr., 1996, Sax's Dangerous Properties of
Industrial Materials. 9th ed. Vols I-III. Van Nostrand
Reinhold, New York.
? MSDS Information Systems Inc., 1996, OHS MSDS on
Disk.
? Muller, Frank. Elf Atochem. Turco Products Division.
Telephone Conversation. November 14, 1995.
? National Center for Manufacturing Sciences, 1995,
Alternatives to Chromium for Metal Finishing, Ann Arbor,
Michigan.
? NIOSH, 1994, NIOSH Pocket Guide to Chemical Hazards.
U.S. Government Printing Office, Washington, DC.
? 40 CFR part 261 et seq.
? 40 CFR part 400 et seq.
? 40 CFR part 129 et seq.
? 42 USC ?412(b)
Point of Contact
John Grainger or Leo Corcoran
Elf Atochem Phone: 215-245-3101
Turco Products Division
7320 Bolsa Avenue
Westminster, CA 92684-3600
Phone: 310-981-8306
B-48 Potential Alternatives Report
B.10.2. Chemcote L497260A (Brent America, Inc.)
Chemcote L497260A is a proprietary chemical conversion coating that offers
corrosion resistance and contact electrical resistance. The overall conversion
coating process is listed below.
1. Cleaning: Brent America, Inc. recommends that Chem-Clean
1220 be used. Chem-Clean 1220 contains potassium hydroxide
and potassium silicate. The bath is maintained at 68癋 to 180癋.
2. Water Rinsing
3. Etching: Brent America, Inc. recommends that Chem-Etch 7002 is
used for etching. Chem-Etch 7002 contains sodium hydroxide.
The bath is maintained at 140癋 to 180癋.
4. Water Rinsing
5. Deoxidizing: Brent America, Inc. recommends that ChemCid 2213
is used for deoxidation of the surface. ChemCid 2213 contains
sulfuric acid, nitric acid, ferric sulfate, and hydrogen peroxide.
6. Water Rinsing
7. Conversion Coating with Chemcote L497260A: The composition
of this bath is proprietary.
8. Water Rinsing
9. Drying
B.10.2.1. Technical Considerations
NCMS issued a study that compared nonchromate conversion coatings to
Alodine 600 and 1200 series coatings (chrome conversion coatings
manufactured by Parker Amchem) on aluminum substrates. Among the
alternatives tested was Chemcote L497260A. Below is a summary of the
findings.
? Corrosion Resistance: Chemcote L497260A exceeded
performance requirements for corrosion resistance tests on
aluminum alloy 6061. However, it did not pass the tests on
alloys 2024 or 7075. Tests followed MIL-C-5541
procedures.
? Contact Electrical Resistance: Chemcote L497260A
passed contact electrical resistance tests on alloy 6061
before a salt spray. Tests followed MIL-C-81706
procedures. Substrates coated with Chemcote L497260A
were also tested until failure after a salt spray. The coatings
had a mean contact electrical resistance of 75.5 m/in2.
? Paint Adhesion: Chemcote L497260A passed dry and wet
paint adhesion tests on aluminum alloys 2024 and 7075. It
also passed the dry paint adhesion test for alloy 6061, but
Potential Alternatives Report B-49
failed wet paint adhesion tests on that alloy. Tests followed
MIL-C-5541 and MIL-C-81706 procedures.
Studies have not been performed to evaluate touch-up techniques.
However, Brent America believes that Chemcote L497260A can be
brushed on to repair coatings.
B.10.2.2. Environmental Issues
The Chemcote L497260A process contains three chemicals in the nine-
step process that are regulated as HAPs under Title III of the CAA. One
HAP is in Chem-Etch 7002, and two are in ChemCid 2213. Wastewater
from the process must be neutralized to meet CWA permitting guidelines
for the Metal Finishing Point Source category. Additionally, metals that
may be present in the wastewater from several of the steps, including
Chem-Etch 7002 (aluminum only) and ChemCid 2213, will require further
treatment to ensure proper removal from the wastewater. Sludge from this
process may be required to be managed in accordance with the
requirements of RCRA Subtitle C.
B.10.2.3. Health and Safety Issues
OSHA has set PELs and the ACGIH has set TLVs for chemicals in the
Chemcote L497260A process, as listed in Table B-14.
Table B-14. PELs and TVLs for Chemicals in Chemote L497260A
Process
Chemical OSHA PEL ACGIH TLV
2 mg/m3 (Ceiling)
Potassium Hydroxide None
NIOSH: 2 mg/m3
2 mg/m3 (Ceiling) 2 mg/m3 (Ceiling)
Sodium Hydroxide
1 mg/m3 1 mg/m3
Sulfuric Acid
Nitric Acid 2 ppm 2 ppm
Ferric Sulfate None None
NIOSH: 1 mg/m3 as
Fe
Hydrogen Peroxide 1 ppm 1 ppm
Ventilation is required to maintain airborne contaminants below the PELs
and TLVs. In addition, personal protection, such as OSHA-approved
respirators and goggles, is required. Contact lenses cannot be worn in the
area, and impermeable gloves should be worn. ChemCid 2213 gives off
B-50 Potential Alternatives Report
sulfuric acid fumes; sulfuric acid is a suspected carcinogen. Sodium
hydroxide is an experimental genotoxin, and nitric acid is an experimental
animal teratogen. Hydrogen peroxide is a suspected human genotoxin and
an experimental animal teratogen.
B.10.2.4. Additional Supporting Literature
? ACGIH, 1995, Industrial Ventilation: A Manual of
Recommended Practice. 22nd ed. Cincinnati, OH.
? ACGIH, 1991, Documentation of the Threshold Limit
Values and Biological Exposure Indices. 6th ed. Vols I-III.
Cincinnati, OH.
? Enright, David. Brent America, Inc. Telephone
Conversation. April 9, 1996.
? Lewis, Richard J., Sr., 1992, Sax's Dangerous Properties of
Industrial Materials. 8th ed. Vols I-III. Van Nostrand
Reinhold, New York.
? MSDS Information Systems Inc., 1996, OHS MSDS on
Disk.
? National Center for Manufacturing Sciences, 1995,
Alternatives to Chromium for Metal Finishing, Ann Arbor,
Michigan.
? NIOSH, 1994, NIOSH Pocket Guide to Chemical Hazards.
U.S. Government Printing Office, Washington, DC.
? 40 CFR part 261 et seq.
? 40 CFR part 400 et seq.
? 40 CFR part 129 et seq.
? 42 USC ?412(b)
Point of Contact
David Enright
Brent America, Inc.
921 Sherwood Drive
Lake Bluff, IL 60044
Phone: 800-222-8819, x115
Fax: 708-295-8748
B.10.3.Chrome-Free Conversion Coating (Hughes Aircraft Company)
The Hughes' Chrome-Free Conversion Coating (CFCC) process is a treatment
sequence intended to provide a nonchrome "drop-in" replacement for the current
chrome process. The Hughes process is actually comprised of two processes.
Potential Alternatives Report B-51
One of the processes (known as the "Long Form") is intended for use on
aluminum surfaces that will be left bare. An abbreviated version of this process
(known as the "Short Form") is intended for use on surfaces that will be painted
following the CFCC treatment.
The objective of both processes is to strip off the native oxide present on all
aluminum surfaces using a degreasing and deoxidizing series of baths. This is
followed by boiling water seals and immersion in highly diluted baths of salts.
This second set of baths is used to regrow a highly uniform, new oxide layer that
provides the bulk of the corrosion protection for the substrate surface. Remaining
surface imperfections are filled in and sealed using a dilute bath. A final drying
step completes the process.
The Short Form process eliminates the diluted salt sealing baths, stopping after
the boiling water immersion bath is complete.
The CFCC process is a developmental procedure that has been scaled up and
readied for commercial use through a current U.S. Army MICOM program. The
CFCC process uses proprietary chemicals that are commercially available and
inexpensive. A license for royalty-free U.S. government use of the process is
being negotiated. When using the CFCC process, the process steps listed below
are followed for the bare metal protection version, or Long Form.
1. Cleaning: This currently uses step Parker Amchem Ridoline 322,
an aqueous alkaline cleaner.
2. Water Rinsing
3. Deoxidizing: This step uses Turco Liquid SMUT-GO NC.
4. Water Rinsing
5. Proprietary Step
6. Proprietary Seal #1
7. Water Rinsing
8. Proprietary Seal #2
9. GN2 or Air Dry
The process steps listed below are followed for the protection of aluminum alloy
surfaces that will subsequently be painted. This process is known as the Short
Form process.
1. Cleaning: This step uses Parker Amchem Ridoline 322.
2. Water Rinsing
3. Deoxidizing: This step uses Turco Liquid SMUT-GO NC.
4. Water Rinsing
5. Proprietary Step
6. GN2 or Air Dry
B-52 Potential Alternatives Report
B.10.3.1. Technical Considerations
A program to make a full-scale prototype of the Hughes CFCC process has
been funded by MICOM. The results to date are provided below.
? Corrosion Resistance: The CFCC process passed corrosion
resistance tests on aluminum alloy 2024, alloy 6061, alloy
7075, and alloy 1100. Tests followed the procedures in
MIL-C-5541 and MIL-C-81706.
? Paint Adhesion: The CFCC process, when overcoated with
an epoxy primer per MIL-P-23377 or with an epoxy
powder paint (no primer), passed wet tape adhesion tests on
alloys 2024, 6061, 7075, and 1100. Samples coated with
the epoxy primer showed no degradation after 3,000 hours
of salt spray. Powder coated samples showed no
degradation after 3,000 hours of salt spray.
? Contact Electrical Resistance: The CFCC Long Form
process (intended for bare metal exposure) had an average
of 57 m/in2 resistance before salt spray, and an average of
360 m/in2 resistance after salt spray. Tests followed
MIL-C-81706 and MIL-C-5541.
A rework or touch-up procedure has been developed to repair scratches in
the CFCC coating from corroding in a salt fog environment. It should be
noted that a CFCC coating can not be repaired with the present commonly
used Alodine 1200 chrome conversion coating.
B.10.3.2. Environmental Issues
The CFCC process contains one chemical, specifically in the deoxidizing
step, that is regulated as a HAP under Title III of the CAA. Due to the
acidic and basic nature of the wastewater from the CFCC process, the
wastewater must be neutralized to meet CWA permitting guidelines for
the Metal Finishing Point Source category. Sludge from this process may
be required to be managed in accordance with the requirements of RCRA
Subtitle C.
B.10.3.3. Health and Safety Issues
OSHA has set PELs and the ACGIH has set TLVs for chemicals in the
CFCC process, as listed in Table B-15.
Potential Alternatives Report B-53
Table B-15. PELs and TVLs for Chemicals in CFCC Process
Chemical OSHA PEL ACGIH TLV
5 mg/m3
Borax None
NIOSH: 5 mg/m3
2-Butoxyethanol 50 ppm (Skin) 25 ppm (Skin)
Monoethanolamine 3 ppm 3 ppm
15 mg/m3 Total 10 mg/m3 Total
Calcium Silicate
5 mg/m3 Respirable
1 mg/m3 Fe 1 mg/m3 Fe
Ferrous Sulfate
Nitric Acid 2 ppm 2 ppm
1 mg/m3 as Fe 1 mg/m3 Fe
Ferric Sulfate
2.5 mg/m3 as F 2.5 mg/m3 as F
Sodium Biflouride
Table B-16 lists the chemical products of the CFCC process as well as the
constituent chemicals present during the process.
Table B-16. Chemical Products of CFCC Process
Product Constituent CAS Number Percent by
Mass
Ridoline 322 (Parker Borax 01303-96-4 10-30
Amchem)
2-Butoxyethanol 00111-76-2 1-10
Monoethanol- 00141-43-5 1-10
amine
Trisodium 07601-54-9 10-30
Phosphate
Calcium Silicate 01344-95-2 1-10
Turco Liquid SMUT- Ferric Sulfate 10028-22-5 25
GO NC
Sodium Bifluoride 01333-83-1 <5
Nitric Acid 07697-37-2 5
Ferrous Sulfate 07720-78-7 N.A.
N.A. = Not Available
Ventilation is required to maintain airborne contaminants below the PELs
and TLVs. In addition, personal protection, such as goggles, neoprene
rubber gloves, and respirators, is required. Ferrous sulfate is a suspected
human carcinogen. Monoethanolamine, 2-butoxyethanol, and ferrous
sulfate are known human neurotoxins. Mutation data exists for borax,
trisodium phosphate, and ferrous sulfate; monoethanolamine is a known
human genotoxin. Borax, 2-butoxyethanol, monoethanolamine, nitric acid
B-54 Potential Alternatives Report
and ferrous sulfate are experimental animal teratogens and/or reproductive
toxicants. No other known or suspected carcinogens, teratogens,
mutagens, or neurotoxins were noted in the CFCC process.
B.10.3.4. Additional Supporting Literature
? ACGIH, 1995, Industrial Ventilation: A Manual of
Recommended Practice. 22nd ed. Cincinnati, OH.
? ACGIH, 1996, 1996 TLVs and BEIs. Threshold Limit
Values for Chemical Substances and Physical Agents.
Biological Exposure Indices. Second Printing. ACGIH,
Cincinnati, OH.
? Elf Atochem North America, Turco Products Division,
1995. Turco Liquid Smut-go NC Material Safety Data
Sheet, Hughes Aircraft Company, El Segundo, CA
? Ike, Charles. Bulk Chemicals, Inc. Telephone
Conversation. November 22, 1995 and April 9, 1996.
? Lewis, Richard J., Sr., 1996, Sax's Dangerous Properties of
Industrial Materials. 9th ed. Vols. I-III. Van Nostrand
Reinhold, New York.
? MSDS Information Systems Inc., 1996, OHS MSDS on
Disk.
? National Center for Manufacturing Sciences, 1995,
Alternatives to Chromium for Metal Finishing, Ann Arbor,
Michigan.
? NIOSH, 1994, NIOSH Pocket Guide to Chemical Hazards.
U.S. Government Printing Office, Washington, DC.
? Parker Amchem, 1989. Ridoline 322 Material Safety Data
Sheet, Parker Amchem, Madison Hts., MI.
? 40 CFR part 261 et seq.
? 40 CFR part 400 et seq.
? 40 CFR part 129 et seq.
? 42 USC ?412(b)
Point of Contact
Steven Tunick
Hughes Electro-Optical Systems
PO Box 902,
Bldg. E1, MS F157
El Segundo, CA 90245
Phone: 310-616-6096
Potential Alternatives Report B-55
B.10.4. E-CLPS 923 and E-CLPS 923X (Bulk Chemicals, Inc.)
Two alternatives to chrome conversion coating are available from Bulk
Chemicals, Inc.: E-CLPS 923 and E-CLPS 923X. Basically, E-CLPS 923X is E-
CLPS 923 with a proprietary additive. Both alternatives require similar process
steps listed below, which are maintained at ambient temperature.
1. Cleaning: Bulk Kleen 692, which contains phosphoric acid and
monoammonium phosphate, is recommended by Bulk Chemicals,
Inc. Bulk Kleen 695 may also be used for additional cleaning.
Bulk Kleen 695 contains hydroxyacetic acid.
2. Water Rinsing
3. Deoxidizing/Acid Conditioning: Bulk Chemicals, Inc.
recommends using Bulk Kleen 678, which contains hydrofluoric
acid.
4. Water Rinsing
5. Conversion Coating with E-CLPS 923 or E-CLPS 923X: E-CLPS
923 contains fluotitanic acid.
6. Drying: After conversion coating, the coating is cured.
B.10.4.1. Technical Considerations
NCMS issued a study that compared nonchromate conversion coatings to
Alodine 600 and 1200 series coatings (chrome conversion coatings
manufactured by Parker Amchem) on aluminum substrates. Among the
alternatives tested were E-CLPS 923 and E-CLPS 923X. Below is a
summary of the findings.
? Corrosion Resistance: E-CLPS 923 and E-CLPS 923X
failed corrosion resistance tests on aluminum alloys 2024,
6061, and 7075. Tests followed MIL-C-5541 procedures.
? Contact Electrical Resistance: E-CLPS 923 and E-CLPS
923X passed contact electrical resistance tests on alloy
6061 before a salt spray. Tests followed MIL-C-81706
procedures. Substrates coated with E-CLPS 923 and E-
CLPS 923X were also tested until failure after a salt spray.
The E-CLPS 923 coatings had a mean contact electrical
resistance of 8.47 m/in2, and the E-CLPS 923X coatings
had a mean contact electrical resistance of 6.78 m/in2.
? Paint Adhesion: E-CLPS 923 passed the dry paint
adhesion tests on alloys 2024 and 7075, and wet paint
adhesion test on alloy 6061. It failed the wet paint adhesion
tests on alloys 2024 and 7075, and dry paint adhesion test
B-56 Potential Alternatives Report
on alloy 6061. E-CLPS 923X passed the dry and wet paint
adhesion tests on alloys 2024 and 7075, and the dry paint
adhesion test on alloy 6061. It failed the wet paint adhesion
test on alloy 6061. Results were not available for other
aluminum alloys. Tests followed MIL-C-5541 and MIL-C-
81706 procedures.
When a surface is scratched, it may be repaired by cleaning the surface
(with detergent, phosphoric acid, or another cleaning agent), brushing on
the E-CLPS 923 or 923X, curing (e.g., with a hair dryer), air drying, and
then painting as needed.
B.10.4.2. Environmental Issues
The E-CLPS 923 and E-CLPS 923X processes contain two chemicals that
are regulated as HAPs under Title III of the CAA. One HAP is in the
cleaning step and one is in the deoxidizing step. Wastewater from the
process must be neutralized to meet CWA permitting guidelines for the
Metal Finishing Point Source category. In addition, fluoride must be
removed from the wastewater if Bulk Kleen 678 is used. Sludge from this
process may be required to be managed in accordance with the requirements
of RCRA Subtitle C.
B.10.4.3. Health and Safety Issues
OSHA has set PELs and the ACGIH has set TLVs for chemicals in the
E-CLPS 923 and E-CLPS 923X processes, as listed below.
Potential Alternatives Report B-57
Table B-17. PELs and TLVs for Chemicals in E-CLPS 923
and E-CLPS 923X Processes
Chemical OSHA PEL ACGIH TLV
1 mg/m3 1 mg/m3
Phosphoric Acid
2.5 mg/m3 as F
Hydrofluoric Acid 3 ppm as F (Ceiling)
2.5 mg/m3 as F 2.5 mg/m3 as F
Fluotitanic Acid
Ventilation is required to maintain airborne contaminants below the PELs
and TLVs. In addition, personal protection, such as goggles and
respirators, is required. No suspected carcinogens are present during these
processes. However, hydrofluoric acid is an experimental animal
teratogen.
B.10.4.4. Additional Supporting Literature
? ACGIH, 1995, Industrial Ventilation: A Manual of
Recommended Practice. 22nd ed. Cincinnati, OH.
? ACGIH, 1991, Documentation of the Threshold Limit
Values and Biological Exposure Indices. 6th ed. Vols I-III.
Cincinnati, OH.
? Ike, Charles. Bulk Chemicals, Inc. Telephone
Conversation. November 22, 1995 and April 9, 1996.
? Lewis, Richard J., Sr., 1992, Sax's Dangerous Properties of
Industrial Materials. 8th ed. Vols I-III. Van Nostrand
Reinhold, New York.
? MSDS Information Systems Inc., 1996, OHS MSDS on
Disk.
? National Center for Manufacturing Sciences, 1995,
Alternatives to Chromium for Metal Finishing, Ann Arbor,
Michigan.
? NIOSH, 1994, NIOSH Pocket Guide to Chemical Hazards.
U.S. Government Printing Office, Washington, DC.
? 40 CFR part 261 et seq.
? 40 CFR part 400 et seq.
? 40 CFR part 129 et seq.
? 42 USC ?412(b)
B-58 Potential Alternatives Report
Point of Contact
Charles Ike
Bulk Chemicals, Inc.
P.O. Box 186
Mohrsville, PA 19541
Phone: 800-338-2855
Fax: 610-926-6125
B.10.5. Turco 2438-28D (Elf Atochem - Turco Products Division)
The Turco Products Division of Elf Atochem distributes a nonchrome conversion
coating referred to as 2438-28D. The conversion coating process is listed below.
1. Cleaning
2. Water Rinsing
3. Deoxidizing
4. Water Rinsing
5. Conversion Coating with 2438-28D: The chemical mixture, which
is inorganic, contains noncarcinogenic metals. The bath is
maintained at ambient temperature.
6. Drying: Parts are allowed to drip dry for this process.
These coatings are not available commercially to date. However, the process is
currently being patented by Elf Atochem.
B.10.5.1. Technical Considerations
NCMS issued a study that compared nonchromate conversion coatings to
Alodine 600 and 1200 series coatings (chrome conversion coatings
manufactured by Parker Amchem) on aluminum substrates. One
alternative tested was referred to as 2438-28D. Below is a summary of the
findings.
? Corrosion Resistance: 2438-28D coatings exceeded
performance requirements for corrosion resistance tests on
aluminum alloy 6061. However, they did not pass tests on
alloy 2024 or alloy 7075. Tests followed MIL-C-5541
procedures.
? Contact Electrical Resistance: 2438-28D coatings passed
contact electrical resistance tests on alloy 6061 before a salt
spray. Tests followed MIL-C-81706 procedures.
Substrates coated with 2438-28D were also tested until
Potential Alternatives Report B-59
failure after a salt spray. The coatings had a mean contact
electrical resistance of 535 m/in2.
? Paint Adhesion: 2438-28D coatings failed dry and wet
paint adhesion tests on alloys 2024, 6061, and 7075. Tests
followed MIL-C-5541 and MIL-C-81706 procedures.
Touch-up techniques have not been tested for 2438-28D. Elf Atochem
expects that a traditional method, such as using a chrome-containing pen,
will be feasible for repair.
B.10.5.2. Environmental Issues
Although the constituents of this conversion coating process are
proprietary, the mixture contains no ODSs or HAPs. Under the CWA,
wastewater may require neutralization depending on its pH level. In
addition, the metals present in the process may require further treatment to
remove from the wastewater. Sludge from the process baths may be
considered to be a listed hazardous waste under RCRA Subtitle C.
B.10.5.3. Health and Safety Issues
Although the constituents of this conversion coating process are
proprietary, the mixture contains no carcinogens. Turco recommends the
use of gloves, respirators, rubber aprons, and goggles for personnel
working with the cleaning and deoxidizing agents. The presence of human
carcinogens, teratogens, genotoxins, or neurotoxins is unknown.
B.10.5.4. Additional Supporting Literature
? ACGIH, 1995, Industrial Ventilation: A Manual of
Recommended Practice. 22nd ed. Cincinnati, OH.
? ACGIH, 1991, Documentation of the Threshold Limit
Values and Biological Exposure Indices. 6th ed. Vols I-III.
Cincinnati, OH.
? Grainger, John. Elf Atochem. Turco Products Division.
Telephone Conversation. April 10, 1996.
? Lewis, Richard J., Sr., 1992, Sax's Dangerous Properties of
Industrial Materials. 8th ed. Vols I-III. Van Nostrand
Reinhold, New York.
? MSDS Information Systems Inc., 1996, OHS MSDS on
Disk.
? Muller, Frank. Elf Atochem. Turco Products Division.
Telephone Conversation. November 14, 1995.
B-60 Potential Alternatives Report
? National Center for Manufacturing Sciences, 1995,
Alternatives to Chromium for Metal Finishing, Ann Arbor,
Michigan.
? NIOSH, 1994, NIOSH Pocket Guide to Chemical Hazards.
U.S. Government Printing Office, Washington, DC.
? 40 CFR part 261 et seq.
? 40 CFR part 400 et seq.
? 40 CFR part 129 et seq.
? 42 USC ?412(b)
Point of Contact
John Grainger
Elf Atochem - Turco Products Division
7320 Bolsa Avenue
Westminster, CA 92684-3600
Phone: 562-981-8306
Potential Alternatives Report B-61
APPENDIX C
PRELIMINARY ESOH ANALYSIS OF VIABLE ALTERNATIVES
TABLE OF CONTENTS
Page
C.1. INTRODUCTION......................................................................................................... C-1
C.2. BACKGROUND TO ESOH SCREENING................................................................ C-2
C.2.1. Environmental Issues .......................................................................................... C-2
C.2.2. Health and Safety Issues...................................................................................... C-3
C.3. ESOH SCREENING..................................................................................................... C-5
C.3.1. Alodin 2000 (Parker Amchem) ........................................................................... C-5
C.3.1.1. Environmental Issues .............................................................................. C-5
C.3.1.2. Health and Safety Issues.......................................................................... C-7
C.3.2. Alumicoat 6788 (Elf Atochem - Turco Products Division) ................................ C-9
C.3.2.1. Environmental Issues .............................................................................. C-9
C.3.2.2. Health and Safety Issues.......................................................................... C-9
C.3.3. Chrome-Free Conversion Coating (CFCC) (Hughes Aircraft Company)......... C-11
C.3.3.1. Environmental Issues ............................................................................ C-11
C.3.3.2. Health and Safety Issues........................................................................ C-12
C.3.4. Sanchem FP (Sanchem) .................................................................................... C-14
C.3.4.1. Environmental Issues ............................................................................ C-14
C.3.4.2. Health and Safety Issues........................................................................ C-14
C.4. POTENTIAL IMPACT OF ESOH ISSUES OF VIABLE ALTERNATIVES ..... C-17
LIST OF TABLES
Table C-1. Toxicity Ranking (TR) for Alternative Products ................................................ C-3
Table C-2. Hazard Ranking Matrix....................................................................................... C-4
Table C-3. Results of ESOH Screening of Viable Alternatives............................................ C-6
Table C-4. ESOH Analysis of Alodine 2000 ........................................................................ C-8
Table C-5. ESOH Analysis of Alumicoat 6788 .................................................................. C-11
Table C-6. ESOH Analysis of CFCC .................................................................................. C-13
Table C-7. ESOH Analysis of Sanchem FP ........................................................................ C-16
Potential Alternatives Report C-i
C.1. INTRODUCTION
As part of the selection of potential alternatives, each of the viable alternatives was
qualitatively assessed for associated ESOH concerns. This initial assessment was
conducted to determine whether there were any conspicuous ESOH issues that may need
to be addressed when selecting alternatives for testing.
Potential Alternatives Report C-1
C.2. BACKGROUND TO ESOH SCREENING
C.2.1. Environmental Issues
The viable alternatives were also evaluated to determine the extent of their
regulation under the major federal environmental laws. Using available resources,
each alternative was evaluated based on the criteria listed below.
? Air Emissions: Each alternative was analyzed to determine if its
constituents are regulated under the CAA as volatile organic
compounds (VOCs) or HAPs.
? Solid/Hazardous Waste Generation: Each alternative was
evaluated to determine whether its use generates solid waste, and,
if so, whether that waste may be regulated as hazardous or
otherwise, under Subtitle C of the RCRA.
? Wastewater Discharges: Each process was analyzed to determine
whether its use would result in the discharge of any wastewaters
regulated under the CWA. Currently, wastewater discharges from
the conversion coating process are subject to regulation under the
CWA's "Metal Finishing Point Source category." Wastewater
from these operations may also be subject to the more stringent
standards proposed under the new "Metal Products and Machinery
(MP&M) category" (60 Fed. Reg. 28209, May 30, 1995).
? Reporting Requirements: The viable alternatives were examined to
determine whether any of the constituents are required to be listed
in Toxic Release Inventory (TRI) reports under Section 313 of the
Emergency Planning and Community Right-to-Know Act
(EPCRA).
? CERCLA Hazardous Substances: Each alternative was assessed to
determine if its constituents are listed as hazardous substances
under the Comprehensive Environmental Response, Compensation
and Liability Act (CERCLA).
? EPA 17: The constituents of each alternative were compared to the
"EPA 17" list. Those substances on the EPA 17 list have been
targeted by EPA because (1) they are released in large quantities
each year, (2) they are generally identified as toxic or hazardous
pollutants, and (3) pollution prevention practices have the potential
to diminish releases of these chemicals. Substances on the EPA 17
list are likely to be targeted for more stringent regulation.
The regulatory impacts of process alternatives are not easily compared, since it is
impossible to say that a process that emits a hazardous waste sludge is any more
or less desirable than a process that emits a HAP. Therefore, it is not possible to
categorize each of the alternatives based on some type of regulatory ranking
C-2 Potential Alternatives Report
system. However, an alternative that has few regulated constituents will clearly
be preferable to one that has many regulated constituents, so the extent to which
an alternative is regulated should be considered as an element of the down-
selection process.
C.2.2. Health and Safety Issues
Toxicity Ranking: As part of the final ESOH analysis criteria, the viable
alternatives were qualitatively assessed for evident hazards (i.e., toxicity and
exposure). Toxicity was qualitatively reviewed, and each viable product given a
final toxicity ranking of high, medium, or low based on the analysis of available
product information. Parameters reviewed included median lethal concentration
50 (LC50) and/or median oral lethal dose 50 (LD50). The exposure criteria used in
the screening and ranking are OSHA PELs and the ACGIH TLVs. The qualitative
ranking scheme for alternative products is provided in Table C-1.
C-1. Toxicity Ranking (TR) for Alternative Products
TR Descriptive Term LC50 LD50 Single Dose,
(ppm) (per kg Body Mass)
H Highly Toxic < 50 < 50 mg
M Moderately Toxic 50-50,000 50 mg - 5 g
L Relatively Nontoxic > 50,000 >5g
H = High
M = Medium
L = Low
Exposure Ranking: Because ESOH hazard down-selection is a function of
toxicity and exposure, a qualitative exposure ranking scheme is also provided.
The procedure for establishing the exposure ranking scheme is discussed briefly
below.
Exposure can occur only when the potential exists for a receptor to directly
contact released chemical constituents from the identified alternative to the
chrome conversion coating, or if there is a mechanism for released constituents to
be transported to a receptor. Each component (released constituents, mechanism
of transport, point of contact, and presence of a receptor) must be present for a
complete exposure pathway to exist. Without exposure, there is no risk; therefore,
the exposure assessment is a key element when assessing potential risks
associated with a technology alternative. A reliable method of calculating
exposure is by conducting a state-of-the-art risk assessment for the potential
alternative technologies replacing chrome conversion coating.
This report uses a screening and ranking method to account for the toxicity and
potential exposure associated with the alternative technologies. The exposure
Potential Alternatives Report C-3
criteria used in the screening and ranking are the OSHA promulgated PELs and
the ACGIH TLVs. Three exposure ranking levels and associated TLV and PEL
intervals were chosen based on the ACGIH recommendations. The three
exposure ranking levels and the associated TLV and PEL interval levels are:
? High Exposure Level (H): When TLV and PEL values are less that
100 ppm
? Moderate Exposure Level (M): When TLV and PEL values are
between 100 to 500 ppm
? Relatively No Exposure Level (L): When TLV and PEL values are
more than 500 ppm.
Hazard Ranking: A final hazard ranking designation was given to the viable
alternatives based on toxicity and exposure ranking as described above. The
hazard ranking is determined by the matrix shown in Table C-2.
Table C-2. Hazard Ranking Matrix
High TR Medium TR Low TR
High ER H M-H M
Medium ER M-H M L-M
Lower M L-M L
TR = Toxicity Ranking
ER = Exposure Ranking
These judgments are based on available scientific information. Also note that this
assessment is based on a limited scope, and CTC assumes no responsibility for the
safe operation of alternative technologies based on these hazard rankings as
outlined.
C-4 Potential Alternatives Report
C.3. ESOH SCREENING
An ESOH screening was performed for each of the viable alternatives, including Alodine
2000, Alumicoat 6788, CFCC, and Sanchem FP. The results of the ESOH screening are
compared with the baseline process in Table C-3. The hazard ranking for Alodine 2000
is based on the replacement of chromic acid with Deoxalume.
C.3.1. ALODINE 2000 (PARKER AMCHEM)
C.3.1.1. Environmental Issues
? Air Emissions: The Alodine 2000 process contains one
substance that has a constituent listed as a HAP: cobalt
nitrate (found in Parker Amchem PTD-2000-H). There are
no VOCs present in this alternative process.
? Solid/Hazardous Waste Generation: Three substances used
in the Alodine 2000 process may generate waste sludge that
must be disposed of as characteristic hazardous wastes
under RCRA. Deoxalume 2200 (pH=1), Parker Amchem
TD-3072-W (pH=13.1), and Alodine 2600 toner (pH=2-3)
all contain constituents that exhibit the characteristic of
corrosivity. All wastes exhibiting the characteristic of
corrosivity are assigned the EPA hazardous waste ID
number D002.
? Wastewater Discharges: The use of Alodine 2000 does not
appear to result in the discharge of any regulated waste
streams under the CWA.
? Reporting Requirements: The following constituents of
substances used in the Alodine 2000 process are required to
be listed in Toxic Release Inventory (TRI) reports under
EPCRA Section 313: nitric acid (in Deoxalume 2200)
and cobalt nitrate (in Parker Amchem PTD-2000-H).
? CERCLA Hazardous Substances: This alternative process
contains nitric acid (in Deoxalume 2200) which is listed as
a hazardous substance under CERCLA.
? EPA 17: There are no constituents included on the EPA 17
list of chemicals targeted for strict regulation.
Potential Alternatives Report C-5
Table C-3. Results of ESOH Screening of Viable Alternatives
Waste- CERCLA EPA TRI Air Emissions Wastes
a a a
Product TR ER HR water HazSub 17 Report HAPs VOCs Solid Hazardous
Baseline H H H Yes 4 2 4 3 U Yes Yes
Alodine 2000 M H M-H No 1 0 2 1 0 Yes Yes
Alumicoat M M M Yes 0 0 2 0 0 Likely No
6788
CFCCb M M M U 4 0 1 0 0 Yes Yes
Sanchem FP M H M-H Yes 1 0 1 1 U Yes U
a
The toxicity ranking (TR), exposure ranking (ER), and hazard ranking (HR) are described in Appendix C.
b
CFCC is a proprietary process; ESOH analysis is based on information on steps known at this time.
HazSub =Hazardous Substance
M= Medium
H= High
U= Unknown
C-6 Potential Alternatives Report
C.3.1.2. Health and Safety Issues
An overall hazard ranking of medium to high is given to the alternative
Alodine 2000. The medium to high ranking indicates that chemical
toxicity and worker exposure are moderate-to-high ESOH concerns when
using this alternative. Worker exposure controls should be reviewed and
implemented to protect the health and safety of workers using Alodine
2000. Constituents of concern, exposure effects, and each specific ranking
for Alodine 2000 are discussed below.
Constituents of concern used in the Alodine 2000 process include N-octyl-
2-pyrrolidone, sodium metasilicate, nitric acid, hydrogen peroxide, cobalt
nitrate, magnesium acetate, triethanolamine, sodium ammonium vanadate
and surfactants. For information on exposure limits and product
composition (percent weights) see Appendix B. Hydrogen peroxide,
cobalt nitrate, and triethanolamine are suspected human carcinogens.
Hydrogen peroxide is a confirmed human genotoxin. Sodium metasilicate,
nitric acid, hydrogen peroxide and cobalt nitrate are experimental animal
teratogens and/or reproductive toxicants. No other known or suspected
carcinogens, teratogens, mutagens, or neurotoxins were noted in Alodine
2000.
Toxic effects for the constituents of concern may range from irritation, to
liver and kidney damage. Identified oral LD50 and inhalation LC50 for the
chemicals of concern also indicate a moderate level of toxicity. The
lowest oral LD50 value identified for constituents of concern is an oral
LD50 of 434 mg cobalt nitrate/kg of body weight. Ammonium vanadate,
which was used as a surrogate for sodium ammonium vanadate, has an
oral LD50 of 58 mg/kg and an inhalation LC50 or 7.8 mg/m3 (four-hour
exposure for rats). Additional toxicity data are discussed below.
? Acute Effects: Acute effects of exposure to products used
in the Alodine 2000 process may include, but may not be
limited to, the following: irritation of the nose, throat, and
respiratory tract; severe skin irritation, allergic skin
reactions, and aggravation of pre-existing skin disorders;
gastrointestinal damage and burns of the digestive tract;
blood, heart, thyroid, pancreas, and kidney damage; nausea,
vomiting, and diarrhea; and aggravation of breathing or
respiratory tract disease or disorders.
? Chronic Effects: Prolonged or repeated contact and/or
inhalation may lead to dermatitis, obstructive lung disease,
liver and kidney damage, and reproductive toxicity.
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Potential Alternatives Report
Comparison of individual constituents to published toxicity data indicates
moderate toxicity; therefore Alodine 2000 was assigned a medium toxicity
ranking.
Based on published exposure limits (PELs and TLVs), Alodine 2000 was
given high exposure level ranking. The exposure ranking was estimated
from the low level recommended for exposure limits.
Appropriate engineering controls (e.g., local ventilation) should be
employed while using the Alodine 2000 process. Administrative controls
may be appropriate as well (e.g., exposure time limits and job sharing).
Also, all ignition sources should be removed from the area where Alodine
2000 is in use. Personal protective equipment is required for worker
health protection throughout the process, and should include protective
clothing (e.g., chemical goggles or face shield, aprons, boots and
chemical-resistant gloves). Approved fitted respirators are recommended
if exposure limits are to be exceeded. Approved emergency facilities
should also be present (e.g., eye wash, shower, etc.).
The results of the ESOH analysis of the Alodine 2000 process are shown
in Table C-4.
Table C-4. ESOH Analysis of Alodine 2000
Process: Alodine 2000
Manufacturer: Parker Amchem
Toxicity Ranking M
Exposure Ranking H
Hazard Ranking M-H
Regulated Wastewaters No
EPA 17 Constituents 0
Air Emissions ?HAPs 1
Air Emissions ?VOCs 0
Toxic Release Inventory (TRI) 2
Reporting
CERCLA Hazardous Substance 1
Wastes Generated ?Solid Yes
Wastes Generated ?Hazardous Yes
M =Medium
H = High
C-8 Potential Alternatives Report
C.3.2. ALUMICOAT 6788 (ELF ATOCHEM - TURCO PRODUCTS DIVISION)
C.3.2.1. Environmental Issues
? Air Emissions: Alumicoat 6788 does not contain any
constituents that are listed as HAPs or VOCs.
? Solid/Hazardous Waste Generation: While use of
Alumicoat 6788 does not appear to result in the generation
of any hazardous wastes, solid waste sludges may result
and must be disposed of properly.
? Wastewater Discharges: The use of Alumicoat 6788 may
result in the discharge of one regulated waste stream.
Under the CWA, n-methyl-2-pyrrolidone is listed as a
pretreatment pollutant. Pretreatment pollutants must
undergo pretreatment to ensure that their discharge to a
publicly-owned treatment works (POTW) is compatible
with the capabilities of that POTW.
? Reporting Requirements: The following constituents of
substances used in the Alumicoat 6788 process are required
to be listed in TRI reports under EPCRA Section 313:
n-methyl-2-pyrrolidone and isopropanol.
? CERCLA Hazardous Substances: This alternative does not
contain any constituents which are listed as hazardous
substances under CERCLA.
? EPA 17: There are no constituents included on the EPA 17
list of chemicals targeted for strict regulation.
C.3.2.2. Health and Safety Issues
An overall medium hazard ranking is given to the alternative Alumicoat
6788. A medium hazard ranking indicates that chemical toxicity and
worker exposure are moderate ESOH concerns when using this alternative.
Worker exposure controls should be reviewed and implemented to protect
the health and safety of workers using Alumicoat 6788. Constituents of
concern, exposure effects, and each specific ranking for Alumicoat 6788
are discussed below.
Constituents of concern in Alumicoat 6788 include n-methyl pyrrolidone
and isopropyl alcohol. For information on exposure limits and product
composition (percent weights) see Appendix B. Isopropyl alcohol is a
suspected human carcinogen and a known human neurotoxin. Mutation
data exists for n-methyl pyrrolidone and isopropyl alcohol and they are
also experimental animal teratogens and/or reproductive toxicants. No
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Potential Alternatives Report
other known or suspected carcinogens, teratogens, mutagens or
neurotoxins were noted in Alumicoat 6788.
Toxic effects for the constituents of concern may range from irritation to
reproductive toxicity. Identified oral LD50 and inhalation LC50 for the
chemicals of concern also indicate a moderate level of toxicity. The
lowest oral LD50 value identified for constituents of concern is an oral
LD50 of 3,600 mg isopropyl alcohol/kg of body weight. Additional
toxicity data are discussed below.
? Acute Effects: Acute effects of exposure to Alumicoat
6788 may include, but may not be limited to, the irritation
of the eyes, skin, respiratory tract, and gastrointestinal tract.
? Chronic Effects: Prolonged or repeated contact and/or
inhalation may lead to reproductive toxicity.
Comparison of individual constituents to published toxicity data indicates
moderate toxicity; therefore Alumicoat 6788 was assigned a medium
toxicity ranking.
Based on published exposure limits (PELs and TLVs), Alumicoat 6788
was given a medium exposure level ranking. The exposure ranking was
estimated from the moderate level recommended for exposure limits.
Appropriate engineering controls (e.g., local ventilation) should be
employed while using Alumicoat 6788. Administrative controls may be
appropriate as well (e.g., exposure time limits and job sharing). Also, all
ignition sources should be removed from the area where Alumicoat 6788
is in use. Personal protective equipment is required for worker health
protection throughout the process, and should include protective clothing
(e.g., face shield or goggles, gloves, boots and apron made of neoprene or
other impervious material). Approved fitted respirators are recommended
if exposure limits are to be exceeded. Approved emergency facilities
should also be present (e.g., eye wash, shower, etc.).
The results of the ESOH analysis of the Alumicoat 6788 process are
shown in Table C-5.
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Table C-5. ESOH Analysis of Alumicoat 6788
Product: Alumicoat 6788
Manufacturer: Elf Atochem - Turco Products
Division
Toxicity Ranking M
Exposure Ranking M
Hazard Ranking M
Regulated Wastewaters Yes
EPA 17 Constituents 0
Air Emissions - HAPs 0
Air Emissions - VOCs 0
TRI Reporting 2
CERCLA Hazardous Substance 0
Wastes Generated - Solid Likely
Wastes Generated - Hazardous No
M = Medium
C.3.3. CHROME-FREE CONVERSION COATING (CFCC) (HUGHES
AIRCRAFT COMPANY)
C.3.3.1. Environmental Issues
? Air Emissions: Chrome-Free Conversion Coating (CFCC)
does not contain any constituents that are listed as HAPs or
VOCs.
? Solid/Hazardous Waste Generation: One substance used in
the CFCC process may generate waste sludge that must be
disposed of as a characteristic hazardous waste under
RCRA. Turco Liquid Smut-Go NC contains at least one
constituent that exhibits the characteristic of corrosivity.
All wastes exhibiting the characteristic of corrosivity are
assigned the EPA hazardous waste ID number D002.
? Wastewater Discharges: The use of CFCC may result in
the discharge of one type of regulated wastestream. Under
the CWA, ferric sulfate, sodium bifluoride, nitric acid, and
ferrous sulfate (all found in Turco Liquid Smut-Go NC) are
designated as hazardous substances under CWA Section
311. Spills or other discharges of CWA hazardous
substances into navigable waters must be reported when the
amount meets or exceeds the substance's reportable
quantity.
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Potential Alternatives Report
? Reporting Requirements: Nitric acid (in Turco Liquid
Smut-Go NC) used in the CFCC process is required to be
listed TRI reports under EPCRA Section 313.
? CERCLA Hazardous Substances: This alternative process
contains ferric sulfate, sodium bifluoride, nitric acid, and
ferrous sulfate (all found in Turco Liquid Smut-Go NC)
which are listed as hazardous substances under CERCLA.
? EPA 17: There are no constituents included on the EPA 17
list of chemicals targeted for strict regulation.
C.3.3.2. Health and Safety Issues
An overall medium hazard ranking is given to the CFCC process. This
ranking is based on the determination that products used in the CFCC
process have a medium toxicity ranking and a medium exposure ranking.
A medium hazard ranking indicates that chemical toxicity and worker
exposure are moderate ESOH concerns when using this alternative.
Worker exposure controls should be reviewed and implemented to protect
the health and safety of workers using CFCC. Constituents of concern,
exposure effects, and each specific ranking for CFCC are discussed below.
Constituents of concern used in the CFCC process include borax, 2-
butoxyethanol, monoethanolamine, trisodium phosphate, calcium silicate,
ferric sulfate, ferrous sulfate, sodium bifluoride, and nitric acid. For
information on exposure limits and product composition (percent weights)
see Appendix B. Ferrous sulfate is a suspected human carcinogen. 2-
Butoxyethanol, monoethanolamine, and ferrous sulfate are known human
neurotoxins. Mutation data exists for borax, trisodium phosphate, and
ferrous sulfate; monoethanolamine is a known human genotoxin. Borax,
2-butoxyethanol, monoethanolamine, nitric acid, and ferrous sulfate are
experimental animal teratogens and/or reproductive toxicants. No other
known or suspected carcinogens, teratogens, mutagens, or neurotoxins
were noted in CFCC.
Toxic effects for the constituents of concern may range from irritation to
nose tumors. Identified oral LD50 and inhalation LC50 for the chemicals of
concern also indicate a moderate level of toxicity. The lowest oral LD50
and inhalation LC50 values identified for constituents of concern are an
oral LD50 of 319 mg ferrous sulfate/kg of body weight and LC50 of 700
mg/m3 for 2-butoxyethanol (seven-hour exposure). Additional toxicity
data are discussed below.
? Acute Effects: Acute effects of exposure to products used
in the CFCC process may include, but may not be limited
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to, the following: irritation of the mouth, throat, and
respiratory tract; eye irritation, burns, and possible
blindness; skin irritation and damage; gastrointestinal tract
damage, nausea, diarrhea, and vomiting; hemolysis;
aggression, somnolence and brain recording changes.
? Chronic Effects: Prolonged or repeated contact and/or
inhalation may lead to blood, kidney, lung and liver effects,
reproductive toxicity, and nose tumors.
Comparison of individual constituents to published toxicity data indicates
moderate toxicity; therefore CFCC was assigned a medium toxicity
ranking.
Based on published exposure limits (PELs and TLVs), CFCC was given a
medium exposure ranking. The exposure ranking was estimated from the
moderate level recommended for exposure limits.
Appropriate engineering controls (e.g., local ventilation) should be
employed while using CFCC. Administrative controls may be appropriate
as well (e.g., exposure time limits and job sharing). Personal protective
equipment is required for worker health protection throughout the process,
and should include protective clothing (e.g., safety glasses with
nonperforated sideshields and impervious gloves). Approved fitted
respirators are recommended if exposure limits are to be exceeded.
Approved emergency facilities should also be present (e.g., eye wash,
shower, etc.).
The results of the ESOH analysis of the CFCC process are shown in
Table C-6.
Table C-6. ESOH Analysis of CFCC
Process: CFCC
Manufacturer: Hughes Aircraft Company
Toxicity Ranking M
Exposure Ranking M
Hazard Ranking M
Regulated Wastewaters Unknown
EPA 17 Constituents 0
Air Emissions - HAPs 0
Air Emissions - VOCs 0
(Table C-6 continued on next page)
Table C-6. ESOH Analysis of CFCC (Continued)
Process: CFCC
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Potential Alternatives Report
Manufacturer: Hughes Aircraft Company
TRI Reporting 1
CERCLA Hazardous Substance 4
Wastes Generated - Solid Yes
Wastes Generated - Hazardous Yes
M = Medium
C.3.4. SANCHEM FP (SANCHEM)
C.3.4.1. Environmental Issues
? Air Emissions: Sanchem FP uses potassium permanganate
(found in Safeguard 3000) which is listed as a HAP under
the general category of manganese compounds. It is
unknown if any VOCs are involved in the Sanchem FP
process.
? Solid/Hazardous Waste Generation: The Sanchem FP
process utilizes Safeguard 3000, which contains potassium
permanganate, a regulated manganese compound. Use of
this substance may generate waste sludge that must be
disposed of as a hazardous waste under RCRA.
? Wastewater Discharges: The use of Sanchem FP may
result in the discharge of one type of regulated wastestream.
Under the CWA, potassium permanganate (in Safeguard
3000) is designated as a hazardous substance under CWA
Section 311. Spills or other discharges of CWA hazardous
substances into navigable waters must be reported when the
amount meets or exceeds the substance's reportable
quantity.
? Reporting Requirements: The following constituent of a
substance used in the Sanchem FP process is required to be
listed in TRI reports under EPCRA Section 313: potassium
permanganate (in Safeguard 3000).
? CERCLA Hazardous Substances: This alternative process
contains potassium permanganate (in Safeguard 3000)
which is listed as a hazardous substance under CERCLA.
? EPA 17: There are no constituents included on the EPA 17
list of chemicals targeted for strict regulation.
C.3.4.2. Health and Safety Issues
C-14 Potential Alternatives Report
An overall medium-to-high hazard ranking is given to the alternative
Sanchem FP. A medium-to-high hazard ranking indicates that chemical
toxicity and worker exposure are moderate to high ESOH concerns when
using this alternative. Worker exposure controls should be reviewed and
implemented to protect the health and safety of workers using Sanchem
FP. Constituents of concern, exposure effects, and each specific ranking
for Sanchem FP are discussed below.
Constituents of concern in Sanchem FP include sodium bromate,
aluminum nitrate, lithium nitrate, and potassium permanganate. For
information on exposure limits and product composition (percent weights),
see Appendix B. Mutation data exists for potassium permanganate and it
is also an experimental animal teratogen/reproductive toxicant. No other
known or suspected carcinogens, teratogens, mutagens, or neurotoxins
were noted in Sanchem FP.
Toxic effects for the constituents of concern may range from irritation to
reproductive toxicity. Identified oral LD50 for the chemicals of concern
also indicate a moderate level of toxicity. The lowest LD50 value
identified for constituents of concern is an LD50 of 140 mg sodium
bromate/kg of body weight. Additional toxicity data are discussed below.
? Acute Effects: Acute effects of exposure to Sanchem FP
may include, but may not be limited to, the irritation of the
eyes and skin, dyspnea, nausea, and other gastrointestinal
effects.
? Chronic Effects: Prolonged or repeated contact and/or
inhalation may lead to reproductive toxicity.
Comparison of individual constituents to published toxicity data indicates
moderate toxicity; therefore Sanchem FP was assigned a medium toxicity
ranking.
Based on published exposure limits (PELs and TLVs), Sanchem FP was
given a high exposure level ranking. The exposure ranking was estimated
from the low level recommended for exposure limits.
Appropriate engineering controls (e.g., local ventilation) should be
employed while using Sanchem FP. Administrative controls may be
appropriate as well (e.g., exposure time limits and job sharing). Also, all
ignition sources should be removed from the area where Sanchem FP is in
use. Personal protective equipment is required for worker health
protection throughout the process, and should include protective clothing
(e.g., goggles and rubber gloves). Approved fitted respirators are
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Potential Alternatives Report
recommended if exposure limits are to be exceeded. Approved emergency
facilities should also be present (e.g., eye wash, shower, etc.).
The results of the ESOH analysis of the Sanchem FP process are shown in
Table C-7.
Table C-7. ESOH Analysis of Sanchem FP
Product: Sanchem FP
Manufacturer: Sanchem
Toxicity Ranking M
Exposure Ranking H
Hazard Ranking M-H
Regulated Wastewaters Yes
EPA 17 Constituents 0
Air Emissions ?HAPs 1
Air Emissions ?VOCs Unknown
TRI Reporting 1
CERCLA Hazardous Substance 1
Wastes Generated ?Solid Yes
Wastes Generated ?Hazardous Unknown
M = Medium
H = High
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C.4. POTENTIAL IMPACT OF ESOH ISSUES OF VIABLE ALTERNATIVES
The reason for finding an alternative to chrome conversion coatings is to eliminate the
use of hexavalent chrome which is known to cause cancer in humans. Care must be
taken, however, not to replace one hazard with another. Alternatives that received a high
hazard ranking should only be considered if no other technically acceptable alternative is
found, and then only after a detailed ESOH review to verify improved ESOH
performance over the present baseline process. Though the viable alternatives screened
contain fewer regulated substances, all alternatives will require changes in engineering
controls to insure the safety of the workers using the chemicals.
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APPENDIX D
REFERENCES
REFERENCES
? 40 CFR part 261 et seq.
? 40 CFR part 400 et seq.
? 40 CFR part 129 et seq.
? 40 CFR part 302 et seq.
? 42 USC ?412(b)
? 42 USC ?1023
? ACGIH, 1996, 1996 TLVs and BEIs. Threshold Limit Values for Chemical
Substances and Physical Agents. Biological Exposure Indices. Second Printing.
ACGIH, Cincinnati, OH.
? Elf Atochem - Turco Products Division, 1995. Alumicoat 6788 Material Safety
Data Sheet, Elf Atochem - Turco Products Division, Westminster, CA.
? Elf Atochem North America, Turco Products Division, 1995. Turco Liquid Smut-
go NC Material Safety Data Sheet, Hughes Aircraft Company, El Segundo, CA
? Lewis, Richard J., Sr., 1996, Sax's Dangerous Properties of Industrial Materials.
9th ed. Vols. I-III. Van Nostrand Reinhold, New York.
? NIOSH, 1994, NIOSH Pocket Guide to Chemical Hazards. U.S. Government
Printing Office, Washington, DC.
? Parker Amchem, 1992. Deoxalume ?2200 Additive Material Safety Data Sheet,
Parker Amchem, Madison Hts., MI.
? Parker Amchem, 1994. PTD-2000-H Material Safety Data Sheet, Parker
Amchem, Madison Hts., MI.
? Parker Amchem, 1994. PTD-2000-I Material Safety Data Sheet, Parker Amchem,
Madison Hts., MI.
? Parker Amchem, 1995. Alodine 2000 Material Safety Data Sheet, Parker
Amchem, Madison Hts., MI.
? Parker Amchem, 1995. Alodine 2600 Toner Material Safety Data Sheet, Parker
Amchem, Madison Hts., MI.
? Parker Amchem, 1995. Deoxalume ?2200 Material Safety Data Sheet, Parker
Amchem, Madison Hts., MI.
? Parker Amchem, 1995. PTD-3095-Y Material Safety Data Sheet, Parker
Amchem, Madison Hts., MI.
? Parker Amchem, 1995. Ridoline 53 LF Material Safety Data Sheet, Parker
Amchem, Madison Hts., MI.
? Parker Amchem, 1989. Ridoline 322 Material Safety Data Sheet, Parker
Amchem, Madison Hts., MI.
? Sanchem, 1990. Sanchem 500 Material Safety Data Sheet, Sanchem, Chicago, IL.
? Sanchem, 1990. Sanchem CC-1000 Material Safety Data Sheet, Sanchem,
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? Sanchem, 1994. Safeguard 2000 Material Safety Data Sheet, Sanchem, Chicago,
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? U.S. EPA, EPA's 33/50 Program Fifth Progress Update.
Potential Alternatives Report D-1
? W.R. Grace and Co-Conn, 1993, Daraclean 282 Material Safety Data Sheet,
Lexington, Massachusetts.
? Witco, 1991, Isoprep 188 Material Safety Data Sheet, New Hudson, Michigan.
? Witco, 1987, Iridite Material Safety Data Sheet, New Hudson, Michigan.
D-2 Potential Alternatives Report
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