Effect of heat treatment on the microstructure, LBE corrosion resistance, and bonding strength of the FeCrAl-based coatings

The bonding strength and LBE corrosion resistance of the Fe15Cr11Al2Si, Fe15Cr11Al0.5Y, and Fe15Cr11Al2Si0.5Y coatings heat-treated at 500-650 degrees C for 500 h were investigated. The results showed that the as-deposited Fe15Cr11Al0.5Y coating has the strongest bonding strength with the F/M steel cladding tube compared with the Fe15Cr11Al2Si and Fe15Cr11Al2Si0.5Y coatings. Heat treatment deteriorates the bonding performance of the coatings, and obvious enrichment of Cr and Al elements appeared. The consumed Al element inside the heat-treated coatings promotes the formation of Fe3O4 on the surface of the coatings after the corrosion test. The Y element can inhibit the enrichment of elements and the formation of Fe3O4. The bonding strength of the heat-treated coatings can be improved after the corrosion test. The underlying mechanism of the evolution of microstructure and properties of the coatings after heat treatment and corrosion test was discussed. Heat treatment deteriorates the bonding performance of the coatings. The bonding strength of the heat-treated coatings can be improved after the corrosion test. The Y element can inhibit the enrichment of elements and the formation of Fe3O4. image