Microstructure Evolution and Wear Resistance of Laser-Clad M2 High-Speed Steel Coatings

Wear is one of the most common failure modes for metals, and therefore the development of low-cost coatings with enhanced wear resistance is of great importance. In the present work, M2 high-speed steel (HSS) coatings, constituted by martensite, carbides, and retained austenite, were prepared by laser cladding on 1045 carbon steel. The microstructure evolution, wear resistance, and wear mechanism of the M2 HSS coatings were systematically investigated. A possible microstructural evolution of the coating during the laser-cladding process is proposed. The prepared M2 HSS coatings exhibit enhanced hardness and wear resistance compared with the 1045 carbon steel substrate. It was found that the wear of the M2 HSS coating is dominated by abrasive wear, adhesive wear, and oxidation wear, while that of the 1045 carbon steel substrate is mainly dominated by oxidation wear. This work provides insight into the morphology evolution and the wear mechanism of the HSS coating prepared by laser cladding.