Effect of WC Content on the Wear and Oxidation Resistance of a WC Reinforced Co50 Laser Clad Layer on H13 Steel
M-Y. Liu, Y-F. Sun, P-X. Xu, X-S. Du and J-W. Feng
WC/Co50 composite coatings have been prepared by laser cladding on a H13 steel substrate. The microstructure, phase composition, microhardness, wear resistance, as well as oxidation resistance of the composite coating, were investigated. The results show that the Co50 coating is mainly composed of γ-Co solid solution, M23C6, Cr7C3, FeNi3, and Co3W. After adding WC, the Co3W phase is replaced by the CCo2W4 phase. The average microhardness and wear resistance of the WC/Co50 composite coating increased continuously with the increase of WC due to the grain refinement strengthening and the second phase strengthening, and the highest microhardness reach 732.6 HV0.2. The oxidation resistance of the clad layer also improved when the WC addition is in the range of 0 to 10 wt.%. When the content of WC is 10 wt.%, the wear resistance and oxidation resistance of the coating are optimal.
Keywords: High power diode laser (HPDL), H13 steel, laser cladding, powder, Co50, WC, microstructure, phase composition, microhardness, wear resistance, oxidation resistance