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Information × Registration Number 0223U001918, 0118U003448 , R & D reports Title "Physical and methodical fundamentals for obtaining and using new materials in space" popup.stage_title Head Fedorov Oleh Р., Доктор фізико-математичних наук Registration Date 06-02-2023 Organization Space Research Institute of National Academy od Science and State Space Agency of Ukraine popup.description2 Objects of research-models of structure of crystal-melt phase boundary at directed solidification in conditions of microgravity; conditions of stability of the flat front of crystallization; elastometers with segregation distribution of hybrid filler, radiation influence on properties of composites, model of accelerometer. The aim of the work is to develop innovative theoretical and experimental research in the direction of space material sciences. Methods of research are phenomenological models of directional solidification; means of experimental and theoretical physics and chemistry of high molecular compounds. The following results are obtained: A) a mathematical model has been developed, which allows to study the stability of the flat phase boundary at the directional solidification taking into account the influence of the density change on the phase boundary and thermal transfer through the solid phase. It is shown that the flow of fluid phase, caused by a density change, plays a major role in the loss of the stability of crystallization front and is realized for perturbation with any wave number k > 0. B) The results of analysis of mechanical and electrical properties of composites with segregated distribution of individual and hybrid fillers of different types are obtained and the cyclic dependence of deformation and current on the applied mechanical loading is analyzed; new piezoresistive hybrid material is synthesized, whose sensitivity parameter relative to deformation almost ten times exceeds known from literature indicators. In order to improve the properties of the second piezo-resistive nanocomposites, the effect of gamma-radiation on the physical properties of the polymer sensor material with carbon nanotubes has been analyzed; the accelerometer model was built and its main characteristics were determined. The obtained nanomosomposite serves as the basis for practical use of such materials as active elements of sensors. Product Description popup.authors Zhyvolub Yevgeniy Kirnisova Margarita Klimenko Yurii Mashkovskii Anatolii Semenov Lev Fedorov Oleh popup.nrat_date 2023-02-06 Close