New Glass Ceramic Sealants for SOFC

Abstract

Glasses from the system MO (M=Mg, Ca)-Al2O3-BaO-SiO2-B2O3 were developed and evaluated as SOFC sealants. The glasses presented in this study are analysed by dilatometry, differential thermal analysis (DTA), hot-stage microscopy and high temperature x-ray diffraction. Microanalysis of the glass to metal interfaces is done by high resolution scanning electron microscopy (SEM). The materials presented in this paper show a good thermal expansion match with metallic interconnect materials, especially the glass with the code G018-305 has an excellent match with Crofer22H between the glass transition temperature Tg and room temperature. The developed glass ceramic composites have a high remaining residual glass phase of 60 wt.% compared to 40wt.% crystals, which primarily consist of Ba4Si6O16-silicates.