Research on Microstructure and Performance of Laser Cladding Fe-based Alloy Coating on Surface of Cr12Mo1V1 Steel

Taking Cr12Mo1V1 steel as base material, selecting Fe-based alloy powder as cladding material, the laser cladding test was carried out on the surface of the substrate by synchronous powder feeding. The microstructure and properties of the cladding layer were analyzed by metallographic microscope, scanning electron microscope（SEM）, microhardness testers and friction and wear testers. The results show that there is a bright region at the junction between the cladding layer and the substrate. The bottom is mostly composed of cell crystals. There are more dendrites and coarse columnar crystals in the middle of the cladding layer, and more equiaxed crystals appear at the top of the cladding layer. The average hardness of the substrate is measured to be 241.78 HV, the average hardness value of the cladding layer is 493.22 HV, and the hardness of the cladding layer is 2.04 times of that of the substrate, indicating that the hardness of the cladding layer is significantly higher than that of the substrate. The average friction coefficient of the matrix is 0.456, and the average friction coefficient of the cladding layer is 0.375, which indicates that the friction coefficient of the cladding layer is slightly lower than that of the substrate.