FRICTION AND WEAR BEHAVIOR OF DIAMOND FILMS COMPARED WITH BULK DIAMOND

摘要

The superior technical properties of bulk diamond in wear-resistant application have driven the expectation that diamond film and diamondlike carbon films (DLC) could posses similar properties. Coated diamond and diamondlike films have great application in biomedical instrumentation sector. They can be used as optical, friction-reducing, corrosion-preventing and wear-resistant coatings. Since the properties of synthesized materials are in large measure determined not only by their compositions, but also by the method of processing and their resultant microstructure, it is of interest to compare the tribological properties of PCD and DLC films with those of natural diamond. Most of the tribological studies have indicated the strong effect of several scales of surface roughness on friction. For example, the sliding friction coefficients of certain PCD surfaces against steel and sapphire can be ten times higher than that of smooth diamond surfaces under similar conditions. The residual stresses on the surface of the coating layer and the integrity between the substrate and the coating have great impact on their wear properties. The purpose of this study is to compare the tribological properties of diamond films with those of bulk diamond.