Ceria containing 20 mol% samaria is a solid electrolyte with potential application in solid oxide fuel cells operating at intermediate temperatures (~500 to 700 ºC) due to its high ionic conductivity. One of the main concerns related to this solid electrolyte is the relatively low sinterability. In this work, two alternative sintering methods were used to obtain ceramic samples with high density, homogeneous microstructure and controlled grain size. Other purpose of this work was to correlate the observed effects in the microstructure and densification with the electrical conductivity of sintered samples. Commercial Ce0.8Sm0.2O1.9 was used as starting material. The consolidation was accomplished by uniaxial and isopressing followed by sintering in air. Several techniques were used for sample characterization. Apparent density results revealed that both sintering methods were able to produce samples with relative density higher than 92%. The electrical conductivity of grains and grain boundaries were similar in these samples, although different grain sizes were obtained.
densification; grain size; electrical conductivity; samaria-doped ceria
