Abstract: Normal and edge-profiled textured nitrogen and silicon co-incorporated diamond-like carbon (N-Si-DLC) films with protrusion area densities of 35%, 44% and 58% were prepared by laser ablation, polishing and sputter, RF-CVD methods. The tribological properties of the textured films against the 316L stainless steel ball in air environments under RH 15%, 45% and 75% were investigated by a ball-on-disk type reciprocating tribometer. The finite element method was used to analyze the stress distribution at the contact surfaces in the steady state of sliding. The results show that the edge-profiled textured N-Si-DLC films possess lower friction and wear compared to the normal textured films. The friction and wear showed positive relation to the maximum contact stress appeared at the edge of protrusions. By edge-profiling, the maximum contact stress and sequential friction and wear could be reduced markedly. The reduction effect of edge-profiling is closely related to the protrusion area density and the best effect was obtained for the films with a protrusion area density of 44%.

Key words: diamond-like carbon (DLC) films, edge-profiling, texture, self-lubrication, contact stress