Oxidation behavior of Fe–16Cr alloy interconnect for SOFC under hydrogen potential gradient

Iron–chromium heat-resisting alloy is a candidate for interconnect of planar-type solid oxide fuel cells (SOFC). The oxidation kinetics of Fe–16Cr alloy (SUS430) has been studied in an air/alloy/fuel (Ar–H2–H2O gas mixture) atmosphere under a hydrogen potential gradient at 1073 K. The growth rates of chromia scale at both sides are almost the same, although oxygen partial pressures of both sides are quite different and a small amount of hydrogen permeates from the fuel side to the air side. The growth rate and microstructure of the scale are practically unaffected by hydrogen potential gradient in Fe–16Cr alloy under the condition simulating SOFC at 1073 K.