Effect of the simultaneous addition of lanthanum and nickel on the oxidation behavior and related area-specific resistance of ferritic stainless steels for solid oxide fuel cell interconnects

The effects of simultaneous lanthanum and nickel addition on the oxidation behavior and area-specific resistance (ASR) of stainless steels for fuelcell interconnects were investigated. The La and Ni addition promoted the entire growth of the oxide layer and increased the roughness of the metal/oxide interface. Despite the thicker oxide scale, these alloys prevented the increase of ASR compared to the alloy with only Ni added. The void analysis indicated that simultaneous La and Ni addition could prevent void growth, leading to lower ASR. The above findings can be interpreted in terms of the fast La diffusion and convoluted metal/oxide interface.