AlCoCrFeNi high-entropy alloys have good mechanical properties, wear resistance, and corrosion resistance, which can be used as a coating material for vulnerable parts. AlCoCrFeNi and AlCoCrFeNi+WC(5wt%) high-entropy alloy powders were pretreated by mechanical powder mixing, and afterwards the coatings were prepared by laser melting on the surface of 45# steel, in order to further improve its performance. The surface morphology, microstructure, element distribution, microhardness, friction wear, and corrosion resistance of the two coatings were com-paratively studied. The results show that the surface roughness of the AlCoCrFeNi+WC(5%) coating is lower, that the coating still has a body-centered cubic structure (BCC/ B2) and that the grain structure of the coating has been refined, with W and Cr elements concentrated at the grain boundaries. The average microhardness of the coating was increased from 500HV to 600HV due to the combined effect of fine grain strengthening and second phase strengthening. The Si3N4 sphere with 4 mm diameter was selected as the friction substrate and tested under a load of 10 N for 30 min. The doping of WC reduced the friction coefficient from 0. 8 to 0. 6, the wear weight loss was reduced by 0. 84 mg, the width and depth of wear scratches were minimized, and the wear level was lighter, compared with those of the AlCoCrFeNi coating. In the electrochemical test with a 3. 5wt% NaCl solution, the self-corrosion potential of the WC-doped coating increased by 0. 042 V, while the self-corrosion current density reduced by one order of magnitude, and the WC-doped coating exhibited a larger capacitive arc diameter. After the test, the AlCoCrFeNi+WC (5%) coating showed lighter corrosion, and the corrosion pits on its surface were significantly reduced. These results indicate that the addition of nano WC can effectively improve the wear and corrosion resistances of the AlCoCrFeNi high-entropy alloy coating. © 2022 Cailiao Daobaoshe/ Materials Review. All rights reserved.
