Experimental Investigation of the Initial Stage of the Oxidation Mechanism of Co Coating for Solid Oxide Fuel Cell Interconnects at 650 °C

The evolution of Co coating in solid oxide fuel cells (SOFCs) under low and medium temperatures (<700 °C) is different from that high temperatures. In this context, the oxidation corrosion 441 ferritic stainless steel (FSS) with a air 650 °C was investigated. results indicated oxidized rapidly Co3O4 spinel layer formed initial exposure 5 min, which improved resistance steel. After at for 120 h, Cr2O3 thickness 0.2–0.4 μm observed on surface bare steel, while scale Co-coated samples composed an inner Fe2O3 solution (0.1–0.3 thick), intermediate (Fe, Co)3O4 outer layer, respectively. sample exhibited better electrical properties. area-specific (ASR) 3.73 mΩ·cm2, 25.4% lower than as mΩ·cm2. Furthermore, thermal growth process protection mechanism were discussed.