TENSILE TEST OF CORRUGATED 8-YSZ THIN-FILMS FOR SOFC

Spatial fluctuations in temperature in planar solid oxide fuel cells(SOFCs) cells, and differences in the thermal expansion coefficients between ceramic electrolyte and metal cell component materials affect the performance and durability of planar SOFC stacks. In this study, We developed a method to prepare 8mol%Y2O3-ZrO2(8YSZ) thin films having corrugated structures to release the thermal stresses. Ni foil substrates were corrugated by folding, and 8YSZ thin films were deposited on the substrates by electron beam evaporation. The substrates were dissolved in FeCl3 aqueous solution, and 8YSZ thin films with corrugated patterns were obtained. The tensile strength of the films was measured. The difference in strain between 8YSZ and Ni components at 1000 degrees C was calculated from their thermal expansion coefficients. By comparing the experimental data with the calculated value, it is expected that the thermal stresses can be released by corrugating 8YSZ electrolyte films.