Electroless Ni-Fe-P Alloy on Ferritic Stainless Steel Solid Oxide Fuel Cell Interconnect

In this study, Ni-Fe-P alloy layer was deposited on the ferritic stainless steel by means of a cost-effective technique of electroless method. After thermal exposure at 800°C in air corresponding to the environment of the SOFC cathode, the oxidation kinetics indicated that the mass gain of steel with Ni-Fe-P alloy layer was higher than that of the steel substrate on which a Cr₂O₃ layer was mainly grown. A double-layer oxide scale with a NiO/(Ni,Fe)₃O₄/(Ni,Cr)₃O₄ outer layer and a protective Cr₂O₃ inner layer was formed on the steel with Ni-Fe-P alloy. The formation of the oxide outer layer was highly desirable to prevent the evaporation of the chromia inner layer developed from the substrate steel, and reduced the scale area specific resistance (ASR).