The effect of sintering on the mechanical properties of SOFC ceramic interconnect materials

Solid oxide fuel cell (SOFC) interconnect materials, strontium and calcium doped lanthanum chromite, were synthesized to investigate the effect of dopant content and sintering temperature on their sinterability. The results show that approximately 96% of the theoretical density could be achieved when LaCrO3, doped with 30 mol% Ca, was sintered in air at 1400°C. However, to get the same sintered density for the strontia doped material, a 1700°C sintering temperature had to be used. The effect of sintering temperature on the fracture strength was also investigated. A maximum fracture strength of 234 MPa for La0.7Sr0.3CrO3−δ and 256 MPa for La0.7Ca0.3CrO3−δwere obtained for both samples sintered at 1700°C.