Session 9: Aerospace/Defense/Military Zinc Nickel Advancements
The aerospace industry has long sought a non-toxic replacement for Cadmium plating. This presentation provides a technical analysis of the variables affecting Zinc-Nickel plating's structure.
Aerospace / Defense / Military
Cadmium plating is a high performance protection layer for steels. It exhibits corrosion protection in extreme environments as well as provides other advantageous properties such as low friction, conductivity, and freedom from voluminous white precipitates. However, Cadmium plating and its traditional hexavalent-chromium-containing post-plate passivation are toxic and banned by many country's environmental laws. Zinc-Nickel, with its Cobalt free passivation treatment, is a high performance, environmentally acceptable alternate to Cadmium plating. Due to risks of hydrogen embrittlement, Zinc-Nickel cannot utilize brighteners and, as such, exhibits a variation in microstructure, visual appearance, and uneven uptake of its passivation treatment. This presentation will provide a summary of the work to understand the variables which contribute to this variation and the results of a full factorial design of experiments (DoE) to characterize their impact. Further, data will be presented on the properties of the output of this DoE including corrosion resistance.