Effect of Atmosphere on Interconnect-Seal Glass Interaction for Solid Oxide Fuel/Electrolyzer Cells
Abstract:In this study, the interaction of an alkaline earth-based silicate glass (SABS-0) with Crofer 22 APU and AISI 441 interconnects has been studied at 800°C for 100 h in argon, air, and H2/H2O atmospheres in order to understand the effect of atmospheres on the interfacial compatibility. Detailed microstructure, diffusion, and phase analyses show that the interfacial compatibility improves from air, to argon, and to H2/H2O atmosphere for the Crofer 22 APU alloy and from H2/H2O, to argon, and to air atmosphere for the AISI 441 alloy. The interfacial compatibility is better for the Crofer 22 APU alloy. Alloy oxidation, elemental interdiffusion, chemical reactions, and glass devitrification occur during the interface formation between the glass and the alloys. The thermal treatment atmospheres mainly affect chromium diffusion and glass devitrification while minor elements influence the oxidation of the alloys and chemical reactions. This work also demonstrates that the high iron content in the AISI 441 alloy is detrimental but the minor impurities such as silicon and aluminum may be beneficial for the interfacial compatibility.
Document Type: Research Article
Affiliations: Department of Materials Science and Engineering, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061
Publication date: March 1, 2011