Sintering and property characterization of strontium-doped lanthanum chromite

The sintering of La0.85Sr0.15CrO3 (LSC-15) SOFC interconnect material can be significantly enhanced by doping with transition elements, such as Cu, Co, V and Ni, on the chromium B-site. Optimized compositions yielded densities greater than 93% theoretical after sintering at 1550 degrees C for 2 hours, compared to <70% theoretical for un-doped stoichiometric LSC-15. Detailed XRD and DTA was used in an attempt to establish phenomena responsible for sintering, in particular the presence of low melting temperature second phases. High density materials were also evaluated for thermal expansion and electrical conductivity in air.