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Information × Registration Number 0221U103201, 0118U003109 , R & D reports Title Physical mechanisms of inelastic deformation of nanostructural crystalline materials, high-entropy alloys and polymer compositions under conditions of moderate and deep cooling. popup.stage_title Head Pal-Val Pavel P., Доктор фізико-математичних наук Registration Date 16-02-2021 Organization B. Verkin Institute for Low Temperature Physics and Engineering of the National Academy of Sciences of Ukraine popup.description2  The use of metals and alloys at cryogenic temperatures has significant limitations due to the phenomenon of low-temperature brittleness. The number of traditional alloys, which at cryogenic temperatures have a strength of 1 GPa and high ductility, is extremely small, which significantly limits their use. Therefore, the emergence of a fundamentally new class of materials - multi-element high-entropy alloys (HEA) with adjustable structure and a set of highly functional properties opens up many new opportunities for their practical use. In a wide range of low temperatures 0.5-300 K, experimental studies of the influence of structural parameters on low-temperature mechanical properties of several wind farms were carried out and microscopic mechanisms were established to control their strength, ductility, dynamic elasticity and internal friction under deep cooling. The presence of high-strength and plastic state, which is achieved by creating a specific microstructure due to deformation-induced phase transformations, twinning and doping processes, has been established. The studied HEA have a unique high-strength condition and high ductility, which opens the way to create new high-strength structural materials. A wide range of new and significant improvements in existing properties inherent in metals that make up the class of nanostructured and nanocrystalline (NC) materials, is clearly manifested in the reduction of grain to nanoscale size. Physico-mechanical properties of submicron grains differ from those of nanoscale grains with a grain size of less than 100 nm. To elucidate the physical mechanisms of plastic deformation of bulk NC titanium, it is important to study samples with a monomodal character by grain size distribution. The practical significance of the obtained results lies in the definite influence of the grain size, which varies from micron to nanoscale values, on the characteristics of strength and ductility in a wide range of low temperatures. Product Description popup.authors popup.nrat_date 2021-02-16 Close