Enhanced Properties of Micro Arc Oxidation Coating with Cu Addition on TC4 Alloy in Marine Environment

By contrast with the traditional method of adding hard particles into micro arc oxidation (MAO) coating to improve its wear performance, this study introduced copper into the MAO coating on TC4 alloy by adding copper pyrophosphate to enhance the wear property in a marine environment and the antibacterial property. The results demonstrated that the MAO coating with copper pyrophosphate addition showed a porous structure, and Cu was mainly concentrated around micropores. CuO and Cu2O were formed in this MAO coating. This MAO coating with Cu had a high bonding strength to the substrate. Although the hardness of the coating with Cu had been reduced, it could reduce the friction coefficient and enhance the wear property in simulated seawater due to the lubrication of Cu. Furthermore, this MAO coating with Cu addition had obvious antibacterial and bactericidal effects due to the antibacterial effect of Cu.