Study on tribological properties of carbon fiber surface-enhanced 7075 Al alloy

[Display omitted] •The addition of CF enhances the wear resistance of the 7075 Al alloy surface.•The addition of CF can drastically reduce the COF and wear rate of 7075 Al alloy.•The lubrication effect brought by CF is affected by the CF content and load. In this study, carbon fiber was used to improve the wear resistance of the 7075 Al alloy surface. The tribological properties of carbon fiber reinforced 7075 Al alloy were evaluated on a reciprocating friction tester in water as the environmental medium. The effects of carbon fiber additions and speed on the wear characteristics were explored at 10N and 50N load, respectively. The abraded composite surfaces were analyzed using scanning electron microscopy (SEM). It was found that at 10 N load, the higher the content of carbon fibers in the sample, the lower the coefficient of friction of the sample; at 50 N load, some of the carbon fibers were broken and lost their lubricating effect, which resulted in that the addition of 15 vol% carbon fibers could not reduce the coefficient of friction of the 7075 Al alloy very well, but the sample with 30 vol% still maintained a low coefficient of friction. For 7075 Al alloy, the speed affects the coverage area of aluminum oxide on the friction surface, which in turn affects the coefficient of friction of the samples. The addition of carbon fiber can also effectively reduce the wear rate of 7075 Al alloy.