The sintering and the microstructure of zirconia ceramics prepared by cold
isostatic pressing of nanoceramic powders were studied. Ceramic powders contained 0, 1.5
and 3 mol.% of yttria. It was found that higher compacting pressures (700 MPa) yielded
green bodies with smaller pores, which showed in their better sinterability. After
sintering at 1100° C, the bodies had a density exceeding 90% t.d. and grains below 80 nm.
A critical ratio of the pore size in green bodies to the particle size was established,
which enables sintering zirconia nanopowders of some 10 nm in size at a temperature of
1100°C.
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