Influence of carbon contents on the structure and tribocorrosion properties of TiSiCN coatings on Ti6Al4V

The TiSiCN coatings were fabricated on Ti6Al4V. The effect of carbon contents on the structure and tribocorrosion properties were studied. The coatings consist of TiN, TiC and Ti(C,N) nanocrystallites, amorphous Si3N4, SiC and little amorphous carbon. The coating (11.9 at% C) exhibits maximum hardness of 39.8 GPa and the best tribocorrosion resistance, which is attributed to the special nanocomposite structure, and the lower friction coefficient of the TiSiCN coating associated with the graphitization effect during sliding in atmosphere. Moreover, the results of tribocorrosion indicate that the volume loss of TiSiCN coatings ascribed to main wear loss and a little corrosion loss, and the synergy between wear and corrosion is a key factor in degenerating the TiSiCN coating.