Effect of Laser Power on Microstructure and Properties of Laser Cladding Layer of WC Reinforced Ni35 Alloy

WC reinforced Ni35 alloy ladding layers were prepared on 45 steel surface by laser cladding at different laser powers (1.1, 1.3, 1.5 kW). The effect of laser power on the microstructure and performance of the cladding layer was studied by optical microscope, scanning electron microscope, X-ray diffractometer, micro Vickers hardness tester, friction and wear testing machine, electrochemical workstation, etc. The results show that with increasing laser power, the macroscopic cracks on the surface of the cladding layer decreased, and the dilution rate of the cladding layer increased. With increasing laser power, the microhardness of the cladding layer increased, and the wear loss and friction factor decreased. The wear resistance of cladding layers with different laser powers was better than that of the matrix. When the laser power was 1.5 kW, the average hardness of the cladding layer surface was increased by 270%, and the wear loss and friction factor was reduced by 95.2% and 54.93%, comparing with that of the matrix. With increasing laser power, the self-corrosion potential of the cladding layer decreased first and then increased, and the self-corrosion current density increased first and then decreased. When the laser power was 1.5 kW, the self-corrosion current density of the cladding layer was the smallest, the corrosion resistance was relatively good.