Study on Microstructure and Wear Resistance of Ni60-WC Composite Coatings Fabricated by Plasma-Laser Hybrid Cladding

The efficient fabrication of high-quality Ni60-WC composite coatings with low dilution and defect density remains a challenge for wear-critical tunneling cutters. In this study, a plasma-laser hybrid cladding (PLHC) strategy was developed to fabricate Ni60-40 wt% WC composite coatings, and their microstructures and properties were systematically compared with those produced by plasma cladding (PC) and laser cladding (LC). The PLHC coatings exhibit a low dilution rate of 10.7% and an ultra-low porosity of 0.2%, indicating improved metallurgical integrity. Microstructural analysis reveals that the hybrid energy input effectively suppresses WC dissolution and promotes a refined, uniformly distributed hard-phase network within the Ni-based matrix. As a result, the PLHC coatings achieve a high average microhardness of 1187.83 HV_1.0 and superior wear resistance, with a wear volume of 24.69 × 10^-3 mm³ under a 200 N load, representing reductions of 53.6% and 20.9% compared with PC and LC coatings, respectively. These results demonstrate the effectiveness of plasma-laser hybrid cladding in tailoring the microstructure-property relationship of WC-reinforced composite coatings.