FINITE ELEMENT ANALYSIS OF THE BONDED COMPLIANT SEAL DESIGN - A NEW SEALING CONCEPT FOR USE IN PLANAR SOLID OXIDE FUEL CELLS

A key issue in developing commercially viable planar solid oxide fuel cell stacks is appropriate seal design. We are currently developing an alternative approach to rigid and compressive seal designs that conceptually combines advantages of both techiques, including hermeticity, mechanical integrity, and minimization of interfacial stresses in either of the joint substrate materials, particulary the ceramic. The new seal relies on a plastically deformable metal seal; one that offers a quasi-dynamic mechanical response in that it is adherent to both sealing surfaces, i.e. non-sliding, but readily yields or deforms under thermally generated stresses. In this way, we hope to mitigate the development of stresses in the adjacent ceramic and metal components even when a significant difference in thermal expansion exists between the two materials. Here we employ finite element modeling to assess the potential thermal cycling performance of this design, specifically as it pertains to sealing components with vastly different thermal expansion properties.