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Information × Registration Number 0212U002021, 0109U001334 , R & D reports Title The investigation of the influence of the defective structure and phase state of polycrystals on the relaxation processes under conditions of plastic and superplastic deformation popup.stage_title Head Sirenko Anatoliy Fedotovich, Registration Date 12-01-2012 Organization Kharkov National University named after V.N. Karazin popup.description2 Objects of study - two-dimensional polycrystalline samples of aluminum and of aluminum coated with reinforcing, eutectic alloys of Sn-38mass. % Pb, and Bi-43mass.% Sn. Aim: To investigate the correlation between various relaxation processes and to establish physical nature of the main deformation mechanisms that control the plastic and superplastic deformation of polycrystals. Research methods: mechanical testing under the creep and active loading, the original research methods, scanning electron microscopy using a JSM-6390LV microscope with an INCA-350 attachment for the EDS-analysis and JSM-820 microscope with LINK AN10/85S X-ray microanalysis system, optical microscopy, X-ray analysis, acoustic spectroscopy. The sequence and the development of relaxation processes at all stages of plastic deformation in aluminum foils with a comprehensive titanium nitride coating were determined. The effect of the presence of coating on the coefficient of strain hardening and mechanical properties was investigated. The effect of temperature on the mechanisms and patterns of plastic deformation and on the nature of change of the strain hardening coefficient of two-dimensional polycrystals with different defect structure deformed in a wide temperature range. The results of the research led to obtaining three patents for inventions. The changes of dynamic Young's modulus and the decrement of vibrations caused by the pre-compression and aging of Sn-38% mass.Pb and Bi-43% mass.Sn alloys were studied. The changes of volume ratio of phases and concentration of components in the surface layers of samples were investigated. Differential thermal analysis under heating and action of external stresses was fulfilled. The experiments were carried out with alloys prepared from chemically pure components by casting them on a copper substrate with the following 75% compression by a hydraulic press. Research results are incorporated into courses and special practical works, and are used when the final bachelors and masters works are being carried out. Predictive assumptions about the development of the research object - the further in-depth study of the influence of various factors on the mechanisms of accommodation, relaxation processes and mechanical properties of polycrystals. Product Description popup.authors Бадіян Є. Коршак В. Сіренко А. Тонкопряд А. Шаповалов Ю. Шурінов Р. popup.nrat_date 2020-04-02 Close