Microstructure and wear resistance of AlCoCrFeNiCuSnX high-entropy alloy coatings by plasma cladding

AlCoCrFeNiCuSnX (X = 0,0.03,0.05,0.1,0.2) high-entropy alloy coatings were prepared on the surface of 35CrMo steel by plasma cladding technology. The phase structure, chemical composition, microstructure and wear resistance of the coatings were studied by X-Ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), microhardness test and wear test. The results show that each coating structure is mainly dendrites. And the dendrites region (DR) consists mainly of Fe-based solid solution with BCC structure, while the interdendritic (ID) consists mainly of Cu-rich phase with FCC structure, and a small amount of AlN precipitated phase with HCP structure. The microhardness of the coating increases with the increase of Sn content. The wear resistance of the coating shows a non-linear trend of increasing and then decreasing with the increase of Sn content, and the Sn0.1 coating has the best wear resistance.