Purpose:

The Department of Defense (DoD) is reducing and eventually eliminating its current reliance on cadmium-based coatings for defense systems because of the environmental hazards and potential threats to human health posed by cadmium, a toxic metal and human carcinogen. Due to cadmium's toxicity, compliance with environmental, safety and health regulations is becoming prohibitively expensive. As a result, non-toxic substances must be found to replace the cadmium coatings. Aluminum-manganese may provide the functional performance of cadmium without its detrimental toxic properties. Utilizing a molten salt bath, aluminum-manganese easily and inexpensively can be plated onto components, including internal diameters, complex geometries, and threaded applications. This project will demonstrate the efficacy of electroplated aluminum-manganese coatings in replacing the toxic cadmium coatings.

Description:

Under ESTCP sponsorship, the U.S. Navy, Air Force, and Army will participate in the development of a test protocol to verify the functional performance of aluminum-manganese. The technical performance and life-cycle cost of molten salt-plated aluminum-manganese will be established. Aluminum-manganese will be evaluated for use on high-strength steels in aviation applications, such as landing gears and fasteners, and on hydraulic, rotary, and threaded components. The functional performance evaluation of the aluminum-manganese coatings will assess whether sacrificial corrosion protection and lubricity without a fatigue debit greater than that of cadmium or an increased risk of hydrogen embrittlement as compared to that of cadmium on high strength steels is possible. Life-cycle costs of the aluminum-manganese plating process will be measured based on environmental, safety, and health considerations as well as on capital equipment, facilities, and operational and disposal costs. These costs will be estimated and then verified by the installation and operation of a production scale molten salt-plating demonstration system at the North Island naval aviation depot.

Benefits:

The replacement of toxic cadmium coatings with non-toxic aluminum-manganese coatings will save DoD environmental compliance costs, and will provide protection to human health and the environment. The savings in annual operations costs come entirely from the elimination of hazardous waste disposal costs associated with cadmium plating. (Project Completed - 2006)

Contacts:

Ms. Erin Beck
Naval Aviation Systems Command (NAVAIR)
Materials Division/NAWCAD
Code 4.3.4.1, Building 2188
48066 Shaw Road
Patuxent River, MD 20670
Telephone: (301) 342-6183
Fax: (301) 342-7566
E-mail: becken@navair.navy.mil

Mr. Craig Matzdorf
Naval Aviation Systems Command (NAVAIR)
Materials Division/NAWCAD
Code 4.3.4.1, Building 2188
48066 Shaw Road
Patuxent River, MD 20670
Telephone: (301) 342-9372
Fax: (301) 342-7566
E-mail: matzdorfc@navair.navy.mil