Spark plasma sintering and characterization of bulk nanostructured fully stabilized zirconia: Part II. Characterization studies

Dense fully stabilized cubic zirconia, sintered by the spark plasma sintering (SPS) method, was characterized through hardness, fracture toughness, and electrical impedance measurements. The effect of sintering temperature on hardness and fracture toughness was evaluated. Samples sintered at 1200 °C for 5 min, which had crystallite size of <100 nm, exhibited the highest hardness. Impedance measurements showed an increase in bulk contribution relative to grain boundaries as sintering temperature is increased. Calculation of the activation energy for conduction gave a value, 1.13 eV, in agreement with previously published results.