Validation of Low Hydrogen Embrittlement (LHE) Alkaline Zinc Nickel Electroplating for Steel and Aluminum Electrical Connectors, Back-Shells and Components

Many of the US Department of Defense (DOD) electrical connectors, back-shells and components currently contain cadmium (Cd).Cadmium is a known carcinogen.Furthermore, the cadmium is typically conversion coated with a hex-chromate which is also hazardous.Both the cadmium plating process and its subsequent conversion coating have been proven to be toxic (unlike other processes such as chromium plating, where a hazardous process yields a non-hazardous coating).Consequently, ES3 has conducted research via SBIR topic AF081-101, Development of Cad Plating Replacement with Alkaline Zinc Nickel Electroplating for Threaded Fasteners/Components successfully which showed that LHE alkaline Zn-Ni solution with non-hex chromate conversion coating produces a coating that performs as good as or better than cadmium under corrosion testing, with very good lubricity characteristics and a comparable friction coefficient to that of the Cd plating. The ES3 LHE Alkaline Zn-Ni plating process is producing excellent performance results based upon testing to data for fatigue, adhesion, hydrogen embrittlement and corrosion protection coupons, including lubricity testing on threaded fasteners. In Phase 1 of this project, ES3 will investigate cadmium plating alternatives; specifically, conduct the feasibility study and testing necessary for USAF validation for Steel and Aluminum Electrical Connectors, Back-Shells and Components.