Development of Cad Plating Replacement with Alkaline Zinc-Nickel Electroplating for Threaded Fasteners/Components

Aircraft structure and propeller systems utilize both high and low strength steel, cad plated threaded components and fasteners throughout its structure. Threaded joints and fasteners manufactured from these alloys require sacrificial protective coatings due to the corrosive environment. Cadmium (Cd) has been the baseline coating for such threaded joints and fasteners for many years due to its many desirable functional qualities. In addition to be corrosion protection, cadmium also provide excellent lubricity characteristics; however, cadmium is a toxic metal and known carcinogen that poses environmental and occupational safety and health risks throughout the life cycle of the plated parts. In Phase I of this project, ES3 will investigate cadmium plating alternatives; specifically, the original Dipsol Low Hydrogen Embrittlement alkaline Zn-Ni coating IZ-C17 and its latest derivative IZ-250Y, and conduct the feasibility study and testing necessary for USAF aircraft and propeller system usage by studying torque tension relationships and hydrogen embrittlement. Additionally, production features, such as tank chemistry, and barrel/rack plating techniques will be researched for utilization in a DoD depot or commercial production environment.