Improvement of running-in process of tetrahedral amorphous carbon film sliding against Si_3N_4 under humid air by O_2 plasma post-irradiation

摘要

During running-in, there is drastic wear and the coefficient of friction (CoF) is high, because the interacting surfaces are unstable. Therefore, the running-in period should be shortened to reduce the wear of a film. When a tribofilm forms, the tribological behaviors reach a steady-state. A tetrahedral amorphous carbon (ta-C) film was irradiated with O-2 plasma, to promote tribofilm formation. This reduced the running-in cycles, CoF, and wear rate by 60%, 35%, and 62%, respectively. It was confirmed that the attractive force induced by the high surface energy agglomerated the wear debris generated during the running-in period.