Microstructure evolution and mechanical properties of laser-cladding TiFeNiCuV high-entropy alloy coatings

In order to improve the surface properties of titanium alloys, a novel TiFeNiCuV high-entropy alloy (HEA) coating was prepared on a Ti−6Al−4V (TC4) substrate via laser cladding under different laser powers. The microstructure, microhardness, and friction wear properties of the coatings were systematically investigated. The results showed that at laser powers of 1200 and 2000 W, the microstructure of the coatings exhibited a core–shell dendritic structure. At 2800 W, the coatings displayed a daisy-like eutectic structure. The average hardness of the coatings reached HV 692.281 owing to solid-solution and fine-grain strengthening. Wear mechanisms of the coatings at room temperature primarily involved fatigue and slight oxidation wear. The total volume loss of the coatings was 4.22×10 −3 mm 3 , which was 14.47% that of the TC4, indicating excellent wear resistance.