Electrical and Oxidation Resistance of Surface Oxide of Porous Fe-Cr-Al Alloy for the Application of Metal Supported SOFCs

Monday, 27 July 2015
Hall 2 (Scottish Exhibition and Conference Centre)
H. C. Pham, S. Taniguchi, Y. Inoue (Kyushu University, Fukuoka, Japan), J. T. Chou (Kurume National College of Technology, Fukuoka, Japan), T. Izumi, K. Matsuoka (JX Nippon Oil and Energy Corporation, Japan), and K. Sasaki (Kyushu University)
We investigated property of a FeCrAl type stainless steel as a porous alloy substrate of metal supported SOFCs especially on the cathode side. We confirmed not only good heat resistance but also low electrical resistance at the interface between the porous substrate and La0.6Sr0.4Co0.2Fe0.8O3 (LSCF) coating at 700oC in air. Morphology and crystal structure of the surface oxide layer of the FeCrAl alloy was analyzed by STEM-EDS and TEM in detail to clarify the cause of such a low electrical resistance. Long-term stability of the oxidation resistance of the porous FeCrAl alloy substrate was investigated by increasing operating temperature up to 900oC. Oxidation rate of the alloy at 700oC in air was estimated by the increase in weight, thickness of the surface oxide and electrical resistance.