Optimized wear behavior and oxidative strengthening mechanism of a WC reinforced high entropy composite coatings

WC-reinforced high entropy alloy composite coatings have been recognized for their effectiveness in enhancing the hardness and wear resistance of material surfaces due to their superior mechanical properties. In this work, AlCrFeNi 2 Si 0.5 Mo/WC x (x = 0, 10, 30, 50 and 70 wt%) composite coatings were prepared on the surface of 304 stainless steels by laser cladding. The microstructure, phase composition, microhardness and wear resistance were investigated. The 50 wt% WC-reinforced coating exhibits excellent hardness and wear resistance, featuring a maximum microhardness of 850 HV, a minimum friction coefficient of 0.40, and a minimum wear rate of 0.33 × 10 −5 mm 3 /N·m. Compared to the 304 stainless steel and the coating without WC, the coating containing 50 wt% WC demonstrates an increase in microhardness by 325.0 % and 17.7 %, respectively, and a reduction in wear rate by 99.1 % and 94.3 %, respectively. The introduction of WC particles not only provides structural support for the coating but also facilitates the retention of the oxide layer, protecting the coating from severe friction and wear. This work provides a valuable insight into utilizing high-content WC particles to enhance the hardness and wear resistance of high entropy alloys.