Current-carrying tribological properties and wear mechanisms of Mo-containing Cu alloy coatings produced by laser cladding

Copper alloy-molybdenum coatings were prepared on the surface of Cu-Cr-Zr alloys by laser cladding. The phase and microstructure were observed, and the hardness, conductivity, friction and wear properties under current-carrying conditions were tested. The results indicate that the prepared coatings exhibit good metallurgical bonding with the substrate. The Brinell hardness of the coatings ranges from 60 to 105 HB, and the electrical conductivity ranges from 17 % to 27 % IACS. The primary wear mechanism is abrasive wear and adhesive wear without current, resulting in the detachment of the Mo phase and transfer of the Cu phase during the sliding process. And it shifts to severe adhesive wear under current-carrying conditions, leading to the formation of aluminum deposit on the coatings.