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Information × Registration Number 0220U101392, 0118U000327 , R & D reports Title Physical and technological foundations for creation of ceramic MgO-RE2O3 (RE: Y, La, Lu) nanocomposites of Irtran class for middle IR-region popup.stage_title Head Tolmachov Oleksandr V., Доктор фізико-математичних наук Registration Date 10-02-2020 Organization Institute for single crystals NASU popup.description2 The consolidation conditions of RE2O3 nanopowders (RE: Y, La, Lu, Yb) as model objects of MgO–RE2O3 ceramic system are investigated. The influence of consolidation routes on the structural-phase state of powders of Y2O3–La2O3–Yb2O3 system is established. The influence of sealing impurities on the microstructure and optical properties of Yb:Y2O3 ceramics has been investigated. Ceramics (Y0.93Yb0.05La0.005Zr0.015)2O3 synthesized by vacuum sintering are characterized by optical transmittance of 83% at wavelength of 5000 nm. Lu2O3:Eu3+5at.% nanopowders and ceramics were synthesized. Their luminescent properties were investigated. Physicochemical conditions of formation of amorphous precursors and nanopowders in MgO–Y2O3 system have been determined. MgO–Y2O3 composite nanopowders (1: 1 by volume) were synthesized with self-propagating glycine-nitrate method. The evolution of the MgO–Y2O3 nanoparticles morphology during heat treatment was investigated. It is shown that calcination at temperatures from 800 to 1000°C leads to the formation of nanocrystals with sizes from 20 to 90 nm, respectively. The influence of synthesis temperature on diffusion mass transfer processes and physical properties of MgO–Y2O3 composite nanoceramics was investigated. MgO–Y2O3 nanocomposites were produced by spark plasma sintering. It is shown that increasing the synthesis temperature increases average grain size of both phases due to thermally activated mass transfer processes (Y2O3: 0.16-0.24 μm, MgO: 0.20-0.275 μm). Ceramics are characterized by high density, absence of open pores and uniform phase distribution, which allows the most effective stabilization of ceramics grain size, since each grain is an obstacle to the growth of another phase grain. The optical properties of nanocomposites were investigated. The optical transparency of MgO–Y2O3 nanocomposites (T75% at  = 6000 nm) is realized for average grain size of 200–250 nm, at which the contribution of light scattering at interfacial Product Description popup.authors Bezkrovna Olga M. Vovk Olena O. Voronov Alexei P. Dobrotvorska Mariya V. Dolzhenkova Elena F. Korshikova Tatyana I. Kryvonogov Sergiy I. Kryzhanovska Oleksandra S. Litvinov Leonid A. Matvieievska Neonila A. Nizhankovskiy Sergiy V. Naydyonov Sergiy V. Parkhomenko Sergij V. Pritula Igor M. Sidelnikova Nataliya S. Safronova Nadiia A. Stepanenko Victor M. Tolmachov Oleksandr V. Yavetskiy Roman P. popup.nrat_date 2020-04-02 Close