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The effect of the composition and density of ceramics on the electroconductivity of solid electrolytes Ce1 − xGdxO2 − δ(x = 0.09–0.31) with a submicron (0.1–0.3 µm) grain size, which are prepared from nanosized powders, is investigated. The powders are synthesized by two methods, specifically, by evaporation of a target with the aid of the radiation of a pulsed carbon dioxide laser and by a chemical method of burning. The samples of ceramics are prepared by magnetopulsed or quasi-isostatic (200–500 MPa) pressing and subsequent caking in air at a temperature of 1100–1300°C. It is established that the electroconductivity of the obtained solid electrolytes is higher and the effective activation energy for conduction is considerably lower as compared with analogous electrolytes with a micron grain size.

Nanocrystalline alumina ceramics were prepared by magnetic-pulse compaction followed by pressureless sintering. The relative density of green compacts exceeded 0.7. The medium in which the starting powders were classified (gas, water, or ethanol) was shown to have a significant effect on their sinterability. The effects of Mg and Ti additions on the sintering behavior of Al2O3 were studied under optimized heat-treatment conditions. Mg-doped α-Al2O3 ceramics containing uniformly distributed MgAl2O4 (≃4 wt %) and offering hardness values of up to 24 GPa were prepared. In the course of sintering, the grain size of these ceramics increases from 110 to 300 nm, and their relative density rises from 0.94 to 0.98.