Deposition of iron aluminide through laser direct energy deposition of Aluminum on steel substrate

Abstract

Fe-rich iron aluminides are promising high-temperature oxidation resistant coating materials for steel. This study aims to evaluate the feasibility of depositing Fe-rich iron aluminides on steels through an interfacial reaction between the aluminum, which was deposited using laser direct energy deposition (L-DED), and the substrate. Al-10Si-Mg and AISI 1045 were selected as the aluminum powder and steel substrates, respectively. The interfacial reaction was investigated by varying the laser power and powder feed rate. Fe-rich iron aluminide was successfully deposited under optimal conditions using L-DED, and it exhibited a B2 crystal structure regardless of the Al content. The increase in the laser power and feed rate increased the vertical cracks, which eventually led to the formation of delamination cracks. The Fe-rich iron aluminide exhibited a higher hardness and wear resistance than the steel substrate.