Iron aluminide coatings by an in-situ reaction process

Iron aluminide (Fe3Al) coatings were prepared by a novel reaction process. In the process, the iron aluminide coating is formed by an in-situ reaction between the aluminum powder fed through a plasma transferred arc (PTA) torch and the steel substrate. Subjected to the high temperature within an argon plasma zone, aluminum powder and the surface of steel substrate melt and react to form the iron aluminide coating. The prepared coating was found to be phase-pure iron aluminide that is porosity-free and metallurgically bonded to the steel substrate. It is expected that the principle demonstrated in this process can be applied to the preparation of other intermetallic and alloy coatings.