Structural Evolution and Tribological Properties of WC Particles-Strengthened Nickel-Based Cladding Layers

WC particles-strengthened nickel-based composite cladding layers with free cracks were successfully manufactured on 42CrMo substrate using powder plasma-transferred arc welding. The phase composition, structural evolution, mechanical and tribological properties of the cladding layers with different WC particles content (45% and 65%) were analyzed and characterized using x-ray diffraction (XRD), scanning electron microscopy (SEM), hardness tester and friction wear machine, to establish a strong relationship between WC content, microstructure, mechanical and tribological properties. The results revealed that the cladding layers primarily consisted of γ-Ni/Fe, WC, W₂C, M₇C₃, M₂₃C₆, M₆C, Cr₃C₂ and Ni₃B. WC particles experienced dissolution–diffusion–precipitation process; with the increase of WC added, the secondary carbides are more numerous and larger. The wear mass loss of W1 and W2 was reduced by 66.7% and 84.6% compared to the substrate, and the volume wear rate of W1 and W2 was reduced by 52.9% and 86.4% compared to the substrate in case 3. The wear mechanism is dominant adhesive wear of the substrate. Abrasive wear is the dominant wear mechanism in W1 and W2 at high load and rotation speed.