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Information × Registration Number 0200U001415, 0195U024297 , R & D reports Title Investigation of the structure of micro- and nanocrystalline materials and its influence on the mechanism of their deformation and fracture. popup.stage_title Head Mil'man Yu. V., Registration Date 16-02-2000 Organization Frantzevich Insitute for Materials Science Problems of the Ukranian National Academy of Sciences popup.description2 Object of the investigation - a quasicrystalline Al-Cu-Fe alloy; coatings from powders on Fe base inclined to amorphization; HTSC ceramics Yba2Cu3O7-x+ZrO2; permanent magnets on the base of Fe-Nd-Nb system; WC-Co with various content of C; Mo, Ni in polycrystalline condition and after deformation with shear; Cr - 35wt% Fe alloy. Purpose of the work - the determination of the possibility to increase material mechanical and magnetic properties on account of reducing their structure to micro- and nanolevel by various methods. Method of the investigation - mechanical and micromechanical investigations, tribotechnical measurements, vibromagnetometry, electron microscopy, X-ray investigations. It is shown that the formation of a nanophase in the intergranular space of the superconducting phase allows to increase the strength as well as to deform plastically the HTSC ceramics. The influence of micro- and nanophase on the magnetic characteristics of high-energetic Fe-Nd-B magnets is considered, the influence o f grain dispersity on the coercivity and the intensity of magnetization is analyzed, optimum chemical compositions of magnets have been found. The possibility of obtaining the nanostructure by means of the deformation by high pressure with a shear (using Mo as an example) and mechanical properties of obtained materials are studied. With polycrystalline nickel and a superplastic Al-Zn alloy there is demonstrated the possibility of studying superplasticity characteristics by the indentation technique developed by the authors. In this process the temperature interval of the manifestation of superplasticity and the superplasticity parameter m are determined. The possibility of using a spinodal decomposition for the formation of micro- and nanocrystalline structure with high level of strength and satisfactory plasticity is shown. Structure and properties of disperse-crystalline coatings from powders of alloys inclined to amorphization are studied. Mechanical properties of quasicrystalline materials and coatings o n the base of Al-Cu-Fe are investigated. For the first time the deformation curve of a quasicrystal at room temperature is constructed, and the availability of deformation softening in it is established. Product Description popup.authors popup.nrat_date 2020-04-03 Close