Effect of Rare Earth Y₂O₃ on Microstructure and Properties of Stellite6/WC Composite Coating by Laser Cladding

Stellite6/WC Co-based alloy composite coatings reinforced with different rare earth Y₂ O₃ additions were prepared on the surface of 45 steel substrates by laser cladding synchronous powder feeding method. The effects of different rare earth Y₂ O₃ additions on the phase composition, microstructure, microhardness and friction and wear properties were analyzed by XRD, SEM, microhardness tester and friction and wear tester. The results show that the main phase composition of the composite cladding layer is solid solution γ-Co, CoC_x, M（Cr, Co, Ni）₂₃C₆, W₂C, Cr₇C₃, Cr₃C₂, Y₂O₃, Co₂Y and Y₂ Co₁₇when the addition of Y₂ O₃ is less than 0.9 wt%, and the reinforcement phase decreases when the addition of Y₂ O₃ is more than0.9 wt%. When the Y₂ O₃ addition is 0.9 wt%, the microstructure of the coating is smallest and densest, and the performance is best. The average microhardness of the composite coating is 608.5 HV0.2, the wear resistance is best, and the wear mechanism is mainly slightly abrasive wear.