Research on carbon film doped with chromium on the carbon-carbon composites with SiC interlayer

Carbon/carbon composites have good mechanical properties and preserve excellent biocompatibility, which make them great potential as orthopedic implants in human body. In order to keep stability of the implants and avoid the unknown effect induced by carbon particle which produce by the wear. It is necessary to coat them with hard coating which can reduce the wear and friction coefficient. In this paper, carbon film doped with chromium on the surface of carbon/carbon has been prepared by unbalanced magnetron sputter technology, in which SiC coating served as interlayer. The morphologies, components and structure were characterized by SEM, EDAX, Raman, XPS and XRD. The tribological properties of the film were also measured. The results show that the structure of the film is amorphous. Most of carbon atoms on carbon film are in the form of graphite-like carbon. The friction coefficient of the carbon film is 0.100, which is less than C/C composite (0.133), and the wear of the film is 0.45×10^-6mm³·(Nm)^-1, which is also less than C/C composite (2.48×10^-6 mm³·(Nm)^-1).