Performance regulation of laser-cladded high-manganese steel coatings by laser remelting process

Preparing high manganese steel (HMS) coatings by laser wire cladding (LWC) is cost-effective and efficient, but it is prone to typical defects such as pores and cracks during the process. These defects significantly undermine the coating performance, resulting in increased maintenance costs and prolonged downtime in industrial environments. In related industries, the additional operating costs resulting from this can be as high as 15% annually. To enhance the wear-resistance of the coating, this paper conducts research by using laser surface remelting (LSR) technology as a post-treatment strengthening method. The research shows that when the scanning speed is increased from 2 mm/s to 5 mm/s, the average grain size decreases from approximately 5.2 μm to 1.8 μm, the hardness increases from 549 HV0.3 to 725 HV0.3, and the matrix remains mainly in the austenite phase. Under low scanning speed conditions, manganese evaporation can significantly reduce the stacking fault energy of the layer, induce martensitic phase transformation, and fully utilize the TWIP/TRIP cooperative strengthening mechanism, ultimately improving the wear resistance of the coating. This study confirms that LSR treatment can effectively control the microstructure, strengthening mechanism and wear-resistance of the coating, providing support for expanding the industrial application scope of LWC wear-resistant coatings.