Microstructure and Tribological Properties of In situ-Synthesized WC-Reinforced Ni60 Coatings Prepared by Laser Cladding with Different Scanning Rates

To reduce the decomposition of WC in the composite coatings so as to improve the wear resistance, in situ-synthesized WC-reinforced Ni60 coatings were prepared by laser cladding with different laser scanning rates. The results showed that the composite coating was dense and crack-free and mainly composed of Fe_0.64Ni_0.36, WC and Cr₂N phases. More importantly, the in situ-synthesized WC was uniformly distributed in the matrix phase and the composite coating showed the lowest wear rate of 2.82 × 10⁻⁶ mm³ N⁻¹ m⁻¹ when the laser scanning rate was 200 mm min⁻¹. The improvement in wear resistance of the coating was ascribed to the formation of WC with high microhardness around 2100 HV_0.1 and good bonding with the matrix phase.