Micro-abrasive wear behavior by ball cratering on MAO coating of Ti–25Ta alloy

Surface treatments are widely used techniques to improve the wear resistance of titanium alloys for biomedical applications. Modification by micro-arc oxidation (MAO) creates an oxide ceramic coating of alloy substrate to improve wear resistance. This work investigated the micro-abrasive wear by ball cratering of MAO coatings over Ti-25Ta alloy. For this purpose, the surfaces were worn by steel balls at a load of 2N and a rotation speed of 200 rpm. After 50 min of testing, the depth of the wear reaches the substrate, confirming that the MAO coating has a much lower wear rate. Guided by Archard's law, the wear volume, wear rate, and MAO coating thickness were calculated through wear test.