Wear resistance of NiCr/Cr₃C₂-20%WS₂ coating on titanium alloy by laser cladding

To enhance the wear resistance of Ti6Al4V titanium alloy, and based on NiCr/Cr₃C₂-20%WS₂ composite powders, self-lubricating anti-wear composite coating on titanium alloy was in-situ synthesized by laser cladding. Phase composition, microstructure, microhardness, tribological properties and counter-ball morphologies of the coating were investigated systematically. The results indicate that compared with laser claded NiCr/Cr₃C₂ composite coating (microhardness is 1167 HV0.5), the microhardness of the laser claded NiCr/Cr₃C₂-20%WS₂ composite coating added 20% WS₂ (1076 HV0.5) decreases slightly, however, the anti-wear and friction reduction properties of the coating improves greatly owing to self-lubricating precipitates Ti₂SC and CrS. Meanwhile, wear surface of Si₃N₄ counter-ball is smooth and without obvious plastic deformation, which presents excellent self-lubricating anti-wear properties of the laser claded NiCr/Cr₃C₂-20%WS₂ composite coating.