Effect of WC content on microstructure and properties of laser-cladded in-situ reactive ZrC/ZrB2 composite coatings on zirconium alloy

ZrC/ZrB2 in-situ reinforced composite coatings were prepared by laser cladding on zirconium alloy. The effect of WC content on microstructure and properties of in-situ reactive ZrC/ZrB2 composite coatings were investigated experimentally. The dilution rate and the inhomogeneity of reinforcements distribution were increased by increasing WC content. The increment of WC content contributed to the refinement of the fishbone dendrites. The microhardness and corrosion resistance of the composite coatings decreased with increasing WC content. When the WC content was 15 wt%, the average microhardness of the coating was the highest as 529 HV0.5. Meanwhile, the corrosion potential was the highest and the corrosion current density was the lowest, which were 0.660 V and 1.627 x 10-8 A cm -2, respectively.