An Alternate Corrosion Resistant Coating to be Applied to Magnesium Secondary Power System Parts

Secondary Power Systems (SPS) are highly complex, expensive, and mission-critical components. The current corrosion-resistant coating system fails to adequately protect magnesium SPS components from harsh environments and cannot survive the overhaul process (i.e. aggressive cleaning chemicals and media blasting for paint removal). As a result, SPS parts suffer severe corrosion damage and require expensive repairs and/or replacement. Crevice corrosion around steel inserts/fasteners is exacerbated by the galvanic pair of steel and magnesium. IBC Materials proposes a unique solution that couples Plasma Electrolytic Oxidation (PEO) and Diamond-Like Carbon (DLC) coating technology. With the durable sealed PEO coating system on magnesium, the SPS components will be protected from corrosion, cleaning chemicals and blast media. With a non-conductive DLC coating on steel inserts, the galvanic driving force will be eliminated by stopping electron flow between the magnesium SPS part and the steel insert. In Phase-I, IBC will develop and validate sealed PEO-DLC coating systems at the coupon level, directly comparing results to the current baseline system. Phase-II will continue coupon-level validation, followed by initial scale-up and ground/flight validation of the coating system on actual SPS parts. In Phase-III, the coating system will be further scaled-up and matured for transition to qualified depot-level systems.