Investigation on the influence of particle size on the microstructure and properties of laser-cladded CuSn12 coatings

This study utilized laser cladding technology to fabricate copper alloy cladding layers on the surface of 42CrMo steel using CuSn12 powder with varying particle sizes (25–38, 45–75, and 75–150 μm). The influence of powder particle size on the morphology, microstructure, microhardness, and wear resistance of the cladding layer was investigated. Morphological analysis revealed that the cross section of the cladding layer produced with fine particles contained a significant number of pores distributed at the bottom and upper-middle regions of the layer; the layer fabricated with medium-sized particles exhibited a limited number of pores, primarily at the bottom; and the layer produced with coarse particles had a few unfused pores located at the interface with the substrate. Microhardness and wear resistance varied with changes in particle size, with the medium-sized particle cladding layer demonstrating superior performance in all evaluated properties.