Tribological properties of diamond films and graphite/diamond composite films with dry friction

The tribological properties of diamond films, Graphite/diamond composite films and cemented carbides were compared using a SRV wear testing machine with dry friction. The surface morphologies of the specimens and the wear tracks were observed by scanning electron microscope (SEM) and the wear volumes on the specimens were measured by a profilometer. The influence of frequency on the tribological properties of these materials was also studied. The results showed that for dry friction, the friction coefficients and the wear volumes of graphite/diamond composite films were very close to that of diamond films. For dry friction, the main wear mechanisms of the diamond film and the graphite/diamond composite fill were micro-rupture wear. The wear-resistance of the diamond film was almost ten times that of YG6 cemented carbide at a frequency of 60 Hz. The wear mechanism of cemented carbide to zirconia at higher frequency is no longer adhesive wear but micro-rapture wear.