Yttria stabilized zirconia (8YSZ) powders were subjected to densification studies employing various sintering techniques like spark plasma sintering (SPS), microwave sintering (MWS) and two-stage sintering (TSS). The densification and microstructural evolution of the samples are studied and compared with that of conventionally sintered samples (ramp and hold). Depending on the technique employed the samples were sintered at different temperatures to arrive at a minimum density of 99%TD. Detailed microstructural evaluation indicated that a low temperature densification leading to finer sintered grain sizes (~1 μm) could be achieved by spark plasma sintering followed by the two stage sintering technique with an average sintered grain size of 2.6 microns

Dense alumina ceramics have been fabricated by the colloidal shaping of alumina slurry using methylcellulose as the networking additive. Concentration as low as 0.08 wt% of methylcellulose had been found to be sufficient enough to convert an alumina slurry of 74-75 wt% solid loading, to consolidated shapes by thermal gelation at 701-801C. Cast shapes could be sintered to dense alumina (99% TD) at temperatures in the range of 15001-15251C at a minimum heating rate of 1801C/h. The effect of methylcellulose concentration on the viscosity of suspensions was studied and green strengths of samples are investigated.

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