Fast low-temperature consolidation of bulk nanometric ceramic materials

Dense zirconia and ceria ceramics with grain sizes approaching 10 nm have been obtained using a high-pressure modification of the field activated sintering (spark plasma sintering). Pressures up to 1 GPa and sintering times of 5 min have been used. The densification has been performed at temperatures as low as 930 °C for fully-stabilized zirconia, 815 °C for samaria-doped ceria, and 675 °C for pure ceria. Relative densities greater than 98% were achieved for all materials. The method overcomes the deleterious effect of powder agglomeration, producing fine grain size for these ceramics in bulk form.