Friction and Wear Performances of 7475 Aluminium Alloy after Anodic Oxidation

A layer of oxide film was prepared on the surface of 7475 aluminum alloy by anodic oxidation. The friction and wear performance of the film at different loads were investigated with the friction and wear tests. The atomic binding energy spectrum, the wear morphologies, the surface hardness and the residual stress were analyzed with XPS, SEM, hard meter and XRD stress tester, respectively. The results show that the oxide film on the surface is relatively dense after anodic oxidation, existing in the form of Al2O3, and diffusion type bonding is contained at the interface. The average friction coefficient is decreased after anodic oxidation, indicating that the friction performance is improved. The wear mechanism of the original sample is adhesive wear and tear, accompanied with abrasive wear, and the wear mechanism of the sample after the anodic oxidation is abrasive wear, where high surface hardness is the main factor of the wear resistance.