Effect of heat treatment on microstructure and properties of WC reinforced co-based composite coating on copper

This paper investigated the microstructure and properties evolution of plasma cladded WC reinforced Co-based composite coating on copper at different heat treatment temperatures in air. Results showed that high thermal conductivity of copper substrate led to the dendrite segregation in the bottom region of coating. Solid phase transformation happened on unsteady coatings in high temperature environment or under friction behavior at room temperature, which can eliminate the dendrite segregation and uniform the grain size. Heat treatment improved the mass fraction of the total carbide phase, the average hardness and wear resistance of coating. After heat treatment at 500 ?, the total carbides content was as high as 36.75%, the average hardness of the sample increased from 954.64 HV0.1 to 1277.65 HV0.1 and wear resistance increased by 13.8%.