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Information × Registration Number 0222U003702, 0121U110123 , R & D reports Title Development of modern methods of obtaining and manufacturing of laser ceramic materials and optical components for extreme operating conditions. popup.stage_title Head Yavetskyi Roman P., Доктор технічних наук Registration Date 25-05-2022 Organization Institute of Single Crystals of the National Academy of Sciences of Ukraine popup.description2  The aim of the project was to establish the principles of control of the properties of highly-loaded YAG suspensions and to obtain ceramic products of complex geometry with high optical and thermomechanical properties. The initial morphological and phase state of the initial oxide nanopowders Al2O3 and Y2O3 used in the preparation of stoichiometric mixtures by high-energy grinding were studied. The influence of granulometric composition of powder mixtures on the optical quality of YAG ceramics compacted by cold isostatic pressing and sintered in vacuum was studied. It is shown that the optimal particle size distribution of the powder mixture corresponds to a composition containing stable secondary agglomerates with D90 from 5 to 7 μm. A hemispherical ceramic green body YAG with a diameter of 50 mm and an average thickness of 1.5 mm was produced by the slip casting method followed by vacuum sintering. A model suspension based on a powder mixture of Al2O3 and Y2O3 was used as a slip, which corresponds to YAG stoichiometric composition and possesses the properties of the Newtonian fluid in terms of rheological characteristics. The average grain size of the YAG phase of the ceramic blank is 5-15 μm. It was found that the green body has heterogeneous phase composition and is characterized by single inclusions of the YAlO3 phase (YAP, approximately 5 wt.%, Grain size 15-20 μm). This is due to the fact that during the slip casting process the interparticle liquid is partially removes fine fractions of Al2O3 from the cast layer, which violates the stoichiometry of the green body. Product Description popup.authors Balabanov Anton E. Bovda Vira O. Vorona Ihor O Dobrotvorska Mariya V. Doroshenko Andriy G Kryzhanovska Oleksandra S. Lytvynov Leonid A. Lyubitska Tamara B Matvienko Oksana O. Mateichenko Pavlo V. Parkhomenko Sergiy V. Pletser Oleh О. Safronova Nadiya А. Tymoshenko Arsenii D. Tolmachov Olexandr V Shevela Yurii V. Yavetskyi Roman P. popup.nrat_date 2022-05-25 Close