Microstructure and Properties of Nickel Coatings after Laser Cladding

Fast nickel coatings on Q235 steel were laser cladded using axial continuous wave CO2 laser.The microstructure and phase composition of the coatings before and after laser cladding were analyzed,micro-hardness was tested.The results show that laser cladding could eliminate the pores in the nickel coatings prepared by brush electroplating,improve the compactness,refine the grain and obtain NiO phase in the coatings.All above increased the coating hardness significantly.As the increase of the laser power,the grain of the coating was refined and the microhardness was improved.