A Composite Super-Hydrophobic Coating on M2052 Alloy Exhibiting Corrosion Resistance in the Marine Environment

M2052 (Mn–20Cu–5Ni–2Fe, at.%) alloy is known for its excellent damping and mechanical properties, but its corrosion resistance is lacking. Here, a composite coating was developed by chemically plating a Ni–P amorphous coating followed by electroplating a superhydrophobic nickel (SH Ni) coating. The composite coating exhibits super-hydrophobic properties primarily for two reasons. Firstly, the pinecone-shaped structure on the surface of the Ni–P/SH Ni coating has the ability to trap air, thereby forming an air layer. Secondly, through surface modification with stearic acid molecules, there is a significant reduction in the surface energy of the coating. As a result, the Ni–P/SH Ni coating were effective in reducing the corrosion rate, which can be attributed to the effective filling of the surface pores of the Ni–P coating by the outer Ni film, and the superhydrophobic characteristics of the SH Ni coating. This study provides a new idea for corrosion protection of M2052 alloys in marine environment.