A.P Surzhikov, T.S. Frangulyan, S.A. Ghyngazov

The dilatometry method was used for investigation of kinetics of compaction compacts of ultrafine powders of zirconia obtained at different compaction pressures. Compacts were manufactured under different compaction pressures of Ultrafine composite powders (UCP) of zirconia of the following composition ZrO2 - 3 mol. % Y2O3, synthesized in the Siberian Chemical Combine method of decomposition of aqueous solutions of nitrate salts of zirconium and yttrium in high-frequency discharge. UCP consisted of isolated spherical particles of 10-80 nm which are associate in agglomerate with a loose structure that do not have a regular shape. Samples were prepared by using uniaxial static pressing with a press PGR-10. Kinetic analysis of the obtained compact sealing was performed using a dilatometer DIL 402 C by NETZSCH (Germany). Calcination was carried out in air. Heating and cooling rates were 10 °C/min. Isothermal exposure was carried out at T = 1550 °C. It is established that the bulk of their shrinkage (95%) were on non-isothermal heating step. The temperature dependence of the relative change in the linear dimensions of Samples with their linear heating absent any express or excesses associated with phase transformations m  t. With increasing compaction pressure P (and thus the density of the compact) the proportion of shrinkage attributable to the beginning of isothermal holding is reduced. For compacts prepared at P  350 MPa, the shrinkage on isothermal stage is absent. According Dilatometry can conclude that in step isothermal compact's thickness is increased, and the magnification increases with increasing compaction pressure compacts. It is established that at the same time with increasing compaction pressure decreases the relative density of ceramics and its microhardness.