Yavetskiy R. Physical and Chemical Basis of Obtaining Technology of Transparent Oxide Ceramics (RE1-xEux)2O3 (RE=Y, Lu) and (Y1-xNdx)3Al5O12.

The thesis is devoted to determination of formation regularities of structure, phase composition and properties of nanopowders as well as consolidated materials on the basis of rare-earth oxides (RE1-xEux)2O3 (RE=Y, Lu) and (Y1-xNdx)3Al5O12; to development the physical and chemical basis of obtaining technology of transparent ceramics under the action of high temperatures or high pressures. The physical and chemical principles of design of optical ceramics based on the high-melting oxides of rare earth elements have been established. The obtaining method of (Y0,99Eu0,01)2O3 nanograined ceramics via transformation-assisted consolidation of nanospheres under high pressures has been proposed. The obtaining technology of (Lu0,95Eu0,05)2O3 scintillation ceramics with an average grain size of 50 m and in-line optical transmittance of 50% at =611 nm via vacuum sintering of nanopowders has been optimized. The conceptions of synthesis and consolidation of multi-component oxide powders have been developed. The concepts of control the structural and phase state of highly-doped (Y1-xNdx)3Al5O12 (x?0,04) laser ceramics which are formed during thermal-activated phase transitions. The ceramics possess optical losses of 10-2 cm-1 at 1064 nm, porosity of 10-3 vol.% and laser slope efficiency of 58% under diode-pumping at =807 nm.