Friction and Wear Characteristics of Diamond-Like Carbon (DLC) Coating Used for Machine Elements

In this study, friction and wear tests were performed in order to investigate the effect of sliding velocity and normal load on the friction and wear characteristics of multi-layered diamond-like carbon (DLC) coating used for machine elements (automotive engine tappet, etc). Friction and wear tests against AISI 52100 bearing steel ball were performed under various sliding velocities (0.25, 0.5, 1 and 2 m/s) and normal loads (6.13, 20.7 and 49.0 N). As a result of test, kinetic friction coefficients and wear rates of multi-layered DLC coating and AISI 52100 bearing steel were obtained under each test condition. The result showed that the kinetic friction coefficients and wear rates generally decreased with the increase in sliding velocity and normal load.