Mechanical Characterization of SOFC Anode Support Materials at Operating Conditions

Thursday, 5 October 2017: 08:40
National Harbor 7 (Gaylord National Resort and Convention Center)
P. Stanley, T. H. Hays, and E. D. Wachsman (University of Maryland)
Solid-oxide fuel cells (SOFCs) rely on a good seal between the anode and cathode sides of the cell to function properly. This means that cells must be manufactured, assembled, and sealed in a manner that does not compromise the gas-tight separation of anode and cathode. The mechanical properties of the cell, specifically the anode support layer, must be able to withstand the stresses it is subjected to without cracking. While the specific material and processing conditions can affect the mechanical properties, so can the temperature and oxygen concentration, thus it is of interest to characterize the mechanical properties not only at ambient conditions, but also at elevated temperatures and under reducing environments.

To study these properties, flexural bend tests were performed on gadolinium doped ceria samples at various temperatures and oxygen partial pressures to study their flexural modulus and flexural strength. This was then compared with other characterization and mechanical testing techniques, such as scanning electron microscopy, X-ray diffraction, indentation and impulse excitation techniques, to evaluate what phenomenon are occurring under what conditions. From this work, it can be better understood how a SOFC must be designed and manufactured to be able to withstand stresses while under operating conditions.