Effect of ultrasonic high-frequency micro-forging on the wear resistance of a Fe-base alloy coating deposited by high-speed laser cladding process

In this study, Fe-based alloy coatings were prepared on 27SiMn substrates by laser cladding. To eliminate defects such as insufficient coating precision and excessive residual stress, the effects of ultrasonic high-frequency micro-forging (UH-FM) on coating microstructure and wear resistance were investigated. The experimental results show that the coating's surface roughness and residual stress are significantly reduced after UH-FM. The surface microstructure was broken and refined, and a gradient structure appeared. A part of the fcc phase was transformed into the bcc phase, which increased the resistance of dislocation movement, and the hardness of the coating increased. The width and depth of the abrasion marks and the wear weight loss of the treated coatings were reduced, and the compact oxide layer was distributed more uniformly, indicating that the UH-FM-treated coatings obtained better wear resistance.