Effect of High-Frequency Percussion on the Microstructure and Corrosion Resistance of Fe-Based Alloy Coatings by High-Speed Laser Cladding

Fe-based alloy coatings were prepared by high-speed laser cladding (HSLC) technology, and the surface was subjected to high-frequency percussion by milligram energy treatment (MET). The dendrites at the top of the coatings were smaller, and there was dendrite segregation. After MET, the degree of dendrite segregation of the coatings decreased. The surface profile of the coatings was smoother, and the roughness decreased from 2.643 μm to 0.913 μm. The residual stress of the coatings changed from 306.92 MPa to -92.18 MPa. The electrochemical corrosion behavior in a 3.5% NaCl solution indicates that the MET coatings exhibit higher corrosion resistance. Anti-corrosion mechanism was discussed based on dendrite segregation, residual stress, and roughness.