Influence of Parameters on Microstructure of Composite Coating Fabricated by Laser Cladding of YSZ@Ni Core-shell Nanoparticles

YSZ@Ni core-shell nanoparticles were used to prepare composite coatings on the surface of Ni-based substrate by CO2 laser cladding. Nano-YSZ and YSZ/Ni mixing powders were also used for preparing composite coatings. The influences of laser beam velocity, laser power and powder bed depth on the coating microstructure were investigated in detail. Combined with the analyses of microhardness, the formation mechanism of the coatings obtained at different laser parameters was investigated. Results indicated that the composite coatings prepared by laser cladding YSZ@Ni core-shell nanoparticles on Ni-based alloy were better in the combination with the substrate than those prepared by CO2 laser cladding nano-YSZ and YSZ/Ni mixing powders. According to the effect of the four laser parameters on cladding quality, the powder type had the largest dependency, followed by laser beam velocity and then the laser power. The powder bed depth had minimal impact.