Room and elevated temperature shear strength of sealants for solid oxide fuel cells

The shear strength of glass-ceramic sealants was measured in torsion to aid the developments of robust sealants that can withstand the combined complex stress situation typical for solid oxide fuel cell stacks. The specimens consisted of hour-glass-shaped samples, with the sealant layer in typical application relevant thickness between two steel plates. Partially crystallized sealant materials with either silver particles or 8YSZ fibers as filler material were tested and compared with respect to their shear strength and failure behavior at room and elevated temperatures up to 800 degrees C. The results emphasize the importance of interfacial bonding as well the effect of creep properties of sealant and steel substrates onto the testing results. An outlook on improvements of testing procedure and specimens' geometry is given. (C) 2016 Elsevier Ltd and Techna Group S.r.l. All rights reserved.