Influence of CO2 laser heat treatment on surface properties, electrochemical and tribological performance of HVOF sprayed WC–24%Cr3C2–6%Ni coating

In this investigation, the tribological and electrochemical performances of HVOF sprayed WC–24%Cr3C2–6%Ni coatings before and after laser heat (LH) treatment were investigated. In the wear test, the friction and wear resistance of the coatings were improved significantly with an optimized LH process. The improvement can be attributed to the improved roughness and hardness, as well as the formation of oxide tribofilms. With LH treatment, the local corrosion of the coating had a decrease and the pit corrosion resistance of the WC–24%Cr3C2–6%Ni coating was improved as a result of the decreasing the size and number of the porosities, especially compact interface achieved by LH treatment.