In-situ synthesis of Co_p Cu composite coating by laser cladding

Uniform Co_p/Cu composite coatings were fabricated by laser cladding and rapid solidification technique, and the influences of processing parameters on microstructure were investigated by scanning electron microscope and energy dispersive spectroscopy. The results showed that high undercooling in the laser melting pool was helpful to the liquid phase separation of Cu-Co alloy.Co_p/Cu composite coating with smooth surface can be successfully in situ synthesized when the processing conditions were well controlled.The as-solidified microstructures were characterized by a distribution of small spherical Co-rich particles homogeneously dispersed in the Curich matrix.Co_p/Cu coating was consisted ofγ-Co and Cu-rich solution.With the decreasing of laser heat input, the diameters of spherical particles in coating decreased.The microstructural evolution and refining mechanism of the Co_p/Cu coatings were also discussed.