Department of Physical Materials Science
Head of the Department: Tat’yana E.Konstantinova, doctor of physico-mathematical sciences (062) 311-11-21, tel/fax (062) 337-75-13
Directions of Scientific Researches: Physics and Technology of promising materials. Nano-materials and nano-technologies: investigation of the nano-particle formation in oxide systems in the course of chemical synthesis using intensive physical actions (microwave action, pulse magnetic fields, ultrasound, high pressures); investigation of structural heterogeneity and multi-scale phenomena in complex systems of the á÷ď3 and áď2. Phase transformations. Structure and properties: investigation of an influence of a structure state and a size of structural elements on the mechanisms and regularities of phase transformations in ceramic oxide and metallic materials; investigation of martensite transformations in response to mechanical stresses.
Basic Results
With the help of X-ray analysis, TEM, NMR and EPR, IR-spectroscopy, computer simulation there have been found out the main mechanisms and determined the formation peculiarities of zirconia dioxide nano-crystals from an amorphous hydroxide. It has been shown that the formation of nano-crystals is a multistage process specified by the phenomena of dehydration and dehydroxylation. It comprises a sequence of the formation of ordered mezoscopic structures. It has been found out that using a microwave, pulse magnetic fields and ultrasound actions together with the thermal treatment one can create the conditions to the formation non-agglomerated mono-dispersive nano-particles of a predetermined size in the range from 7 to 25 nm.
On the base of the experimental and theoretical investigations there has been developed an idea of the nature of a tetragonal-monocline transition in nano-crystals ZrO2–3 mol% Y2O3 at a hydrostatic reduction of a powder system under a high pressure which allows the control of sealing and sintering to be done.
There has been found that in the metallic materials with a high dislocation density plastic deformation can be accomplished by the formation of local dipole bends of a crystal lattice which are proposed to consider as volume defects of a mesolevel – “displanations”, and a corresponding deformation mechanism – as a bending one. There has been built up a model of a new mesodefect.
Applied researches
There has been developed a technology of obtaining oxide nano-powders realized for the systems on the base of ZrO2, LaMnO3 and others, (TiO2, in cooperation with the Research and Technical Center “Reaktivelektron”).
Application of nano-powders when producing ceramics extends the service life of ceramic articles more than tenfold. This is confirmed by operational tests (plungers in the hydro equipment at the Zasyad’ko mine in the town of Donetsk).
Scientific cooperation
The Institute of the NAS of Ukraine: G.V.Krdyumov Institute of Physics of Metals (Kiev), I.M.Frantsevich Institute of Materials Science Problems (Kiev), the Research and Technical Center “Reaktivelektron” (Donetsk); the Research and Technical Center “Reaktivelektron” (Donetsk); the Research and Technical Complex “Institut monokristallov” (Kharkov); the Institute of Physical Chemistry of the Polish Academy of Sciences (Warsaw, Poland); University Lion-1 (France); University of Neapole (Italy); the Institute of Physics (Prague, Czecia); D.I.Mendeleev Chemical-Technological University (Moscow, Russia); the Institute of Solid-State Physics and Semiconductors of the NAS of Belarus (Minsk); the National Institute of Materials Science (Tsukuba, Ibaraki, Japan). There are being carried out the work by the international grants (the Ukrainian Research and Technical Center, NATO “Science for Peace”)
Selected publications
1. T.E.Konstantinova. Mesostructure of the deformed alloys. Donetsk. Publ.DonIPhT NAS of Ukraine 170 (1997)
2. T.E.Konstantinova, I.A.Danilenko, N.P.Pilipenko, G.K.Volkova. Nanomaterials for SOFC Electrolytes and anodes on the base of zirconia. Electrochemical Societty Proceedings 1934 (2003-07), 153 (2003).
3. N.V.Tokiy, T.E.Konstantinova, V.V.Tokiy D.L.Savina Influence of oxigen vacancies and 26 d-impurity on electronic and transport properties of zirconia. Electroch. Soc. Proc.1934 (2003-07), 181 (2003).
4. T.E.Konstantinova, I.A.Danilenko, A.A.Dobrikov, G.K.Volkova, V.V.Tokiy, S.Gorban. TEM, ESR and XRD studies of thermally induced formation of nanocrystalline zirconia. Advances in Science and Technology 30, 187 (2003).
5. Y.A.Danilenko, T.E.Konstantinova, G.K.Volkova, A.S.Doroshkevich, V.A.Glasunova. Phase transformation in the synthesis of La0.7Sr03MnO3 nanopowders. Functional materials, 3 (11), 608 (2004).
6. T.E.Konstantinova, Y.A.Danilenko, V.V.Tokiy, G.K.Volkova, V.A.Glasunova, N.V.Tokiy, N.P.Pilipenko, A.S.Doroshkevich, I.K.Nosolev. Nano-powders on the base of zirkonia dioxide: production, study, application. Nano-systems, nano-materials, nano-technologies 2 (2), 609 (2004).
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