Deposition of Fe–Al Intermetallic Coatings on Solid Oxide Fuel Cell (SOFC) Interconnects by Pack Cementation

Iron aluminide intermetallic compounds are well known for their high temperature oxidation resistance. In an effort to increase high temperature oxidation resistance of UNS 430 stainless steel, iron-aluminum intermetallic coatings with high iron content were grown on the substrate by the pack cementation technique. The microstructure and composition of the phases were characterized and the effects of pack cementation process parameters on the aluminide coatings were examined. Optoelectronic evaluation indicated that the formation of different stoichiometries of iron aluminide on the surface is controlled by outward diffusion of elements from the substrate.