<p>Microstructural analysis and electrochemical measurements were performed to study the corrosion resistance in aggressive environments of a fully dense Fe-based coating on low-alloy high-strength bainitic steel substrates via high-speed laser cladding (HSLC). The microstructure results reveal that an ordered grain transformation from the bottom to the top layer is formed, exhibiting a progression from cellular to dendritic and finally equiaxed crystal structures. The segregation of Cr at the interdendritic regions promotes the formation of carbides, particularly the M₇C₃ type, accounting for about 65.1% of the total volume fraction. The hardness of the cladding layer is significantly increased. These carbides form a carbide skeleton with a distinct fishbone morphology during corrosion process, effectively boosting the corrosion resistance of the coating. The smaller carbides act as critical barriers in the corrosion process, substantially decelerating the electrochemical corrosion rate. Moreover, the formation of Cr-rich oxide film on the surface of the coating provides additional corrosion protection, further reducing the corrosion rate. These findings offer essential scientific insights for understanding and improving the performance of corrosion-resistant coatings.</p>