Microstructure and corrosion resistance of Fe-based coatings prepared using high-speed laser cladding and powerful spinning treatment

Abstract

Fe-based alloy coatings are promising for protecting the surface of hydraulic columns because of their excellent corrosion resistance. In this study, Fe-based coatings were prepared using high-speed laser cladding (HSLC) technology, and the outer surface of the coating was subjected to powerful spinning treatment (PST). The grains of the surface layer of the coatings were refined, which increased the volume ratio of intergranular ferrite, and subsequent X-ray diffraction detection revealed more α-phases. Their electrochemical corrosion behaviour in a 3.5% NaCl solution indicated that PST coatings exhibited higher corrosion resistance than the coatings without PST. The anti-corrosion mechanism was discussed based on grain refinement, phase composition, and elemental content.