In this study, the coating was fabricated on the AISI420 stainless steel substrate by laser cladding, and the 18Cr-0.2C Fe-based powder was used in the process. The substrate was close to the heat source exhibited a complex thermal cycle, as evidenced by the significant changes in microstructures and mechanical properties of those regions. The microstructure, phase compositions, mechanical and corrosion properties of the heat-affected zone (HAZ) were investigated systematically. The temperature distribution in the HAZ were accurately calculated. The results show that the microstructure consisted of three areas, HAZ1, HAZ2, and Substrate. The HAZ2 region exhibited agglomerated precipitated M23C6(M=Fe, Cr) carbides, the martensite was partially transformed into ferrite. Moreover, with a large number of corrosion pits that appeared after the salt spray test. Conversely, HAZ1's mechanical and corrosion properties were comparable to those of its substrate, as evidenced by the lack of corrosion pits in HAZ1 or substrate.
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