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Information × Registration Number 0213U002232, 0112U004930 , R & D reports Title Microwave tunable materials, composites, and devices - 984091 popup.stage_title Head Belous Anatolii, Registration Date 21-01-2013 Organization V.I.Vernadskii Institute of General and Inorganic Chemistry NASU popup.description2 Report on the 1st stage of R&D. 32 pp., 12 figs., 1 table. Object of investigation - policrystalline film and composite materials based on ferroelectrics/ relaxors Ba(Ti1-xZrx)O3 (BZT) with the perovskite structure. The objective of R&D - development of new tunable microwave materials, composite structures and microwave components with low dielectric loss and high sensitivity to the applied voltages. In the consequence of the stage 1 of R&D, the synthesis of polycrystalline materials based on the solid solutions Ba(Ti1-xZrx)O3 (BZT) has been carried out. Crystal structure, phase composition, and microstructure of synthesized materials have been studied. Barium titanate (BaTiO3) has been shown to form as the secondary phase during sintering BZT with low zirconium content, whereas in the case of higher zirconium concentration BaTi2O5 forms in the materials. The electrophysical parameters of synthesized materials have been evaluated over wide frequency and temperature ranges. The incresing zirconium concentration in the material composition was found to result in a suppressed dielectric permittivity and substantial (above two orders of magnitude) reduction of dielectric loss. Non-linear tunable parameters of the materials based on BZT have been determined under the bias field. It has been shown that the materials based on BZT demonstrate high tunability coefficient (nR = 50- 60 %) at low strength of the biasing field. Nanosize powders of solid solutions BZT have been obtained by a sol-gel method, and the corresponding chemical transformations have been studied. Single-phase thin BZT films have been deposited on the Al2O3 substrates, and the effect of the gel concentration as well as the number of film layers on the films' quality have been determined. Synthesized nanoparticles have been used for the production of the ceramics which exhibited a potential for the applications as non-linear tunable dielectrics for modern communications. As a result of the project activities, science-technical cooperation between scientists from Ukraine, Slovenia, and UK has been established. OXIDES, FERROELECTRICS, TUNABLE MATERIALS, PEROVSKITES Product Description popup.authors Єленіч Олександр Володимирович В'юнов Олег Іванович Дурилін Дмитро Олександрович Кобилянська Софія Дмитрівна Коваленко Леонід Леонідович Овчар Олег Вікторович Пашкова Олена Володимирівна Плутенко Тетяна Олександрівна Соловйова Катерина Дмитрівна Солопан Сергій Олександрович Ступін Юрій Дмитрович Суслов Олександр Миколайович Хоменко Борис Семенович Янчевський Олег Зігмунтович popup.nrat_date 2020-04-02 Close