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Information × Registration Number 0216U002247, 0115U004261 , R & D reports Title Multifunctional nanostructured titanium alloys popup.stage_title Head Varyukhin Victor Mykolayovych, Registration Date 12-02-2016 Organization Dоnetsk Institute for Physics and Engineering named after O.O.Galkin of the NAS of Ukraine popup.description2 Object of study. The process of severe plastic deformation of powder materials. The purpose of the work. Determination of basic physical mechanisms severe plastic deformation of powder materials by screw extrusion. The method of investigation. Theoretical study. Mathematical modeling. Results. The basic processes that occur during sintering of powder particles awash with titanium forming massive technically pure titanium, phase changes, volume changes and kinetics of hydrogen in the dehydrogenation. Replacement titanium powder titanium hydride provides for activation of diffusion processes and intensifying sintering particles, and thus a reduction of residual porosity. The reason for this is the restoration of surface oxide films by hydrogen and increase the number of defects resulting from volume effects of phase transformations. The intensity of the dehydrogenation process and its stages determined by the rate of diffusion of hydrogen in different phases of system Ti-H. It is shown that titanium hydride powder sintering may form maloporystyy commercially pure titanium, which later will be exposed to intense deformation to modify its structural conditions. The process of extrusion screw powder blanks. The influence of process parameters (back pressure, the presence of a compact metal shell, number of passes) the distribution of porosity and deformation of the material accumulated solid phase. It was established that the presence of back pressure to prevent the growth of porosity and increase the uniformity of its distribution. With increasing number of passes there is an increase in density and size of the accumulated strain. Simultaneously, the alignment occurs by the volume of distribution properties of the product. The shell creates an additional hydrostatic pressure. At the same time, the availability of high-quality membrane does not change the type of porosity distribution by volume of the workpiece. The reasons and consequences of the emergence of multifractal vortices during severe plastic deformation of powder and porous bodies by screw extrusion. It is shown that developed in the pore space of noncompact workpieces causes the emergence of self-similar vortex at different levels of scale. Established that the eddy multifractal phenomena in simple shear during extrusion screw causing differences in the mechanisms strengthening the compact and noncompact materials. Significantly increased compared with concentric lines in the current strain of compact material integral way deformation promotes intensification of accommodation particles of powder mixture components. The intensive mass transfer leads to chemical and structural homogenization and eliminates porosity. Projected use of results of operations. The results can be used to develop technology for new materials with improved performance for medical use. Product Description popup.authors Бейгельзимер Яків Юхимович Дворніков Євген Олександрович Дмитренко Вікторія Юріївна Распорня Дмитро Володимирович Саввакін Дмитро Георгійович popup.nrat_date 2020-04-02 Close