Effect of Al Content on Phase Structure, Wear Resistance, and Corrosion Resistance of FeCoCrNiAl x High‐Entropy Alloy Coatings Prepared by Laser Cladding

To enhance the surface properties and extend the service life of H13 hot‐work tool steel, this study employed laser cladding technology to deposit FeCoCrNiAl x high‐entropy alloy coatings with varying Al contents ( x = 0.3, 0.6, 0.9) onto the H13 steel substrate. The influence of Al content on the coating microstructure, mechanical properties, and corrosion resistance was systematically investigated. Results indicate that as Al content increases, the coatings maintain a single face‐centered‐cubic phase structure. The grain morphology evolves from columnar dendrites to reticular dendrites and cellular grains. Al solid solution strengthening and lattice distortion significantly enhance coating hardness, with the FeCoCrNiAl 0.9 coating reaching 501.78 HV 0.2 approximately 2.33 times that of the substrate. The friction and wear properties improved correspondingly. The FeCoCrNiAl 0.9 coating exhibited a volume loss of 0.215 mm 3 , which was approximately 94.9% lower than that of the H13 substrate, and its wear mechanism was dominated by mild abrasive wear. The FeCoCrNiAl 0.9 coating exhibited the best corrosion resistance in a 5% NaCl solution. This study elucidates the mechanism by which Al content regulates the microstructure and properties of FeCoCrNiAl x coatings, providing crucial insights for developing high‐performance surface‐hardening coatings for hot‐work dies.