Anomalous Corrosion Behavior of Stainless Steels under SOFC Interconnect Exposure Conditions

Abstract

In low and intermediate temperature solid oxide fuel cell (SOFC) stacks, ferritic stainless steels are among the most promising materials to construct the interconnect, which is simultaneously exposed to a fuel on the anode side and an oxidant on the cathode side. However, the corrosion behavior of stainless steels under the interconnect exposure condition was unclear and thus was investigated in a specifically designed apparatus. It was discovered that, under the simultaneous exposure, the oxide scale formed on the air side of the sample was significantly different from the scales formed when the alloy was exposed to air only. It appeared that the anomalous corrosion behavior during the simultaneous dual exposure was due to hydrogen transport through the bulk alloy from the fuel side to the air side. © 2003 The Electrochemical Society. All rights reserved.