Influence of Aluminum content on the microstructure, corrosion property, and tribological performance of cold-sprayed Fe-Al coatings

Fe-Al coatings were deposited on gray cast iron by cold spraying as an exploratory approach for protecting iron relics. The microstructure, deposition efficiency, corrosion property and wear performance of coatings were investigated. Fe-Al coatings completely retained the original composition of mixed powders. Fe particles were surrounded by highly deformed Al particles, and the Fe-50Al coating achieved the highest deposition efficiency (58.6%) and thickness (1.86 mm). Electrochemical tests revealed that the Fe-50Al coating exhibited superior corrosion resistance. Friction and wear tests showed the Fe-50Al coating had the lowest average COF (0.15) owing to its low porosity and distributed soft Al phases. With increasing Al content, the dominant wear mechanism shifted from adhesive to abrasive wear, with oxidative wear present in all coatings.