The Microstructure and Wear Resistance of Laser Cladding Ni60/60%WC Composite Coatings

In this study, Ni60/60%WC composite coatings were fabricated on 45 steel by laser cladding. The optimum process was selected through high throughput optimization experiments which had a laser power of 2400 W, scanning speed of 8 mm/s, and powder feeding rate of 20 g/min. The single-layer multilayer coatings were prepared without any cracks and pores, and the thickness of the coatings was 1.52 mm. The coating and the substrate were found to have an effective metallurgical connection. WC was distributed relatively uniformly throughout the coating, which involved the γ-(Fe, Ni), WC, W2C, Cr23C6, and Fe3.57W9.43C3.54 phases. The average microhardness of the coating was 1416.14 HV0.2, approximately 5.47 times that of the substrate, and the average coefficient of friction of the coating was 0.5144, which was 43.5% lower than that of the substrate. The wear rate was reduced by 79.13%.