▎ 摘　　要

NOVELTY - A zinc-cadmium alloy composite coating comprises a chemically deposited zinc layer, a nickel plating layer, a zinc-cadmium alloy plating layer, a silane chromium-free passivation layer and a graphene sealing layer which are sequentially arranged on the surface of an aluminum alloy substrate. USE - Zinc-cadmium alloy composite coating used for aerospace electrical component. ADVANTAGE - The zinc-cadmium alloy composite coating has excellent corrosion resistance, improved bonding strength, replaces the cadmium plating layer of aerospace component, greatly reduces the pollution of the cadmium to the environment, uses silane chromium-free passivation layer to replace the hexavalent chromium passivation layer with high toxicity, which can avoid the pollution of hexavalent chromium to the environment. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of the zinc-cadmium alloy composite coating.