Laser shock peening Fe-based coatings for enhancing wear and corrosion resistance

Laser Shock Peening (LSP) was introduced to reduce the residual stress and improve the wear and corrosion resistance of Fe-based 43X coating on worn U71Mn steel by laser cladding technology. The tensile stress decreased with increasing of laser power density and impact times, finally, transferred to compressive stress. The microstructure of the coatings was refined due to LSP treatment. The refined microstructure and existence of retained Austenite phase resulted in significant improvement in microhardness and anti-wear performances. The coatings after LSP process presented better corrosion resistance. However, impact three times with a higher power density has negative effect on improving the corrosion resistance.