Simulation of thermal stress within diffusion couple of composite seals with Crofer 22APU for solid oxide fuel cells applications

The appropriate selection of component material is a critical issue for technological development of SOFC. Hence, the main aim of this paper is to investigate the sealing and bonding issues in solid oxide fuel cells (SOFC) using COMSOL multiphysics analysis. Using multiphysics modeling, the stress generated within the composite seal after 10,000 h heat-treatment at 800 °C along with its magnitude was simulated. The thermal stress was also investigated as a function of seal thickness. Interestingly, for all the diffusion couples, no high stress regions were observed at the corners. For most of the GG5 surface, the stress varies between 0.4 and 0.8 N m−2 for seal thickness of 0.5 mm, which is the highest among all samples having same thickness. The heat-flux was simulated in order to investigate if there was any temperature gradient about the interface, or within the layers. Isothermal contours were obtained for the sample GG7 upto 1000 °C for 10,000 h heat-treatment.