Oxidation of Haynes 230 alloy in reduced temperature solid oxide fuel cell environments

Haynes 230 alloy was exposed to reducing and oxidizing environments at 750degreesC for 1000 h, simulating the conditions in a reduced temperature solid oxide fuel cell (SOFC). The oxidized specimens were characterized in terms of the oxide morphology, composition and crystal structure. The oxide scale in each environment was identified as Cr2O3 with the existence of Cr2MnO4. Ni remained metallic in the reducing atmosphere, and NiO was detected in the sample exposed to air. The oxide scale is around 1 mum thick after 1000 h of oxidation in both situations. The area specific resistance (ASR) contributed by the oxide scale is expected less than 0.1 Omega cm(2) after 40,000 h of exposure when a parabolic oxide growth rate is assumed, demonstrating the suitability of the interconnect application of this alloy in the reduced temperature SOFCs. (C) 2004 Elsevier B.V. All rights reserved.