화학공학소재연구정보센터
Journal of Power Sources, Vol.280, 272-288, 2015
Joint strength of a solid oxide fuel cell glass-ceramic sealant with metallic interconnect in a reducing environment
Effects of reducing environment and thermal aging on the joint strength of a BaO-B2O3-Al2O3-SiO2 glass-ceramic sealant (GC-9) with a ferritic-stainless-steel interconnect (Crofer 22 H) for planar solid oxide fuel cells are investigated. A technique is developed for conducting mechanical tests at room temperature and 800 degrees C in H-2-7 vol% H2O under shear and tensile loadings. Given an aged condition and loading mode, the joint strength at 800 degrees C is lower than that at room temperature in the given humidified hydrogen atmosphere. A thermal aging at 800 degrees C in H-2-7 vol% H2O for 100 h or 1000 h enhances both shear and tensile joint strengths at room temperature but degrades them at 800 degrees C in the same reducing environment Non-aged specimens show a comparable joint strength and fracture mode when tested in humidified hydrogen and in air under a given loading mode and testing temperature. The shear strength at 800 degrees C for joint specimens after a 1000-h thermal aging at 800 degrees C in air or humidified hydrogen is reduced by a similar extent of 19%, compared to the counterpart of non-aged joint specimens tested in the same oxidizing or reducing environment. (C) 2015 Elsevier B.V. All rights reserved.