Tribological performances of diamond film and graphite/diamond composite film

In this paper, the tribological performances of diamond film, graphite/diamond composite film, and cemented carbide were compared on a SRV wear testing machine under the conditions of paraffin oil lubrication and dry friction. The surface morphologies of specimens and wear tracks were observed by scanning electron microscope (SEM). The wear volumes on wear tracks were measured by profilometer. Under paraffin oil lubrication, the friction coefficients and wear volumes of graphite/diamond composite film were all lower than that of diamond film. The wear mechanisms of diamond film and graphite/diamond composite film under paraffin oil lubrication were sub-micro-fracture wear. Under dry friction the friction coefficient and wear volumes of graphite/diamond composite film was similar to that of diamond film. The wear-resistance of diamond film was almost ten times that of YG6 cemented carbide under the frequency of 60 Hz.