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Information × Registration Number 0215U001226, 0112U001281 , R & D reports Title Inflience of boron and carbon on the structure and properties of the alloys of rare earth and d-elements and their hydrides. popup.stage_title Head Kotur Bogdan Yaroslavovych, Registration Date 03-02-2015 Organization Ivan Franko National University of Lviv. Journalism Department popup.description2 Research object: Crystal chemistry pecularities, hydrogen sorption, magnetic and electrical properties of the intermetallic compounds of the R-M-X systems (R = La, Ce, Gd, Dy, Er; M = Cr, Mn, Fe, Co, Ni; X = B, C), as well as regularities of material synthesises with the highest possible hydrogen feedback hydrogen capacity depending on component composition and crystal structure of the compounds. Objective: The study of the synthesis regularities of alloys of the R-M-X systems (R = La, Ce, Gd, Dy, Er; M = Cr, Mn, Fe, Co, Ni; X = B, C), crystal chemistry pecularities, magnetic and electrical properties of the compounds of these systems and hydride phases based on them, and use of the obtained results as the theoretical basis for the creation of new magnetic and superconducting materials, and materials with sufficient for practical use feedback hydrogen capacity. Methods: arc melting and homogenizing annealing, gase-pressure method for the synthesis of hydrides, volumetric method of hydrogen sorption properties of the alloys, X-ray phase and structural analyses, microstructural analysis, four-contact method for the electrical resistivity measuring, non-contact resonator method for the surface resistance measuring, the extraction method of magnetic susceptibility measuring. The isothermal sections of phase diagrams of the systems Dy-{Co, Ni}-C and {La, Tb, Dy}-B-C, Dy-{Mn, Fe}-C, Tb-{Mn, Fe, Co, Ni}-C at 800°C and partly at 600°C in full concentration ranges were constructed for the first time. Fragments of state diagrams of three binary R-M systems (Tb-Co, Tb-Fe, Dy-Ni) in high d-element content were refined. Six ternary and five binary compounds were sinthesized and their crystal structures were determined. Concentration compositions of 16 new ternary carbides and borocarbides with unknown structures were localized. Carbon- and hydrogen capacity properties of the compounds Dy2Co17, Dy2Ni17 preserving their initial srystal structure (Th2Ni17-type) were investigated. The hydrogenation of binary carbides Tb2Cand Dy2C, and ternary carbides Tb2Cr2C3 Dy2Mn2-xC5, R2BC was performed. The temperature dependence of the electrical resistivity, specific heat and magnetic properties for Dy2Mn2-xC5 (x = 0.6) were studied. The quasi-binary system DyCoC2-DyNiC2 based on two isomorphic compounds was investigated. An evolution of the magnetic properties crossover from the ferromagnetic compound DyCoC2 to the antiferromagnetic one DyNiC2 within the solid solution was studied and the magnetic phase diagram of this quasi-binary system was built. Crystal structures of La5B2C6 and LaC2 compounds were determined with neutron diffraction techniques. The influence of the nature of the component on phase equilibria in R-M-C and R-B-C systems was investigated suggesting the phase equilibria in related, not yet discovered systems. The regularities of the corrosive activity of the carbides and borocarbides depending on their structural pecularities of the p-element arrangement were determined. The features of hydrogenation of the compounds in R-M-C and R-B-C systems were established. Physical properties and their relationships with the crystal structures of the studied compounds were characterized. The generalization of the results was made and the recommendations of practical use for developind of the new materials were given. As the results of this research 20 articles were published, 13 reports at 9 conferences were presented, 1 manual for students was published and a PhD thesis was presented at the department with recommendation for the defence. Recommendations for further research work in this direction were given. Product Description popup.authors Бабіжецький Володимир Станіславович Гембара Микола Вікторович Котур Богдан Ярославович Левицький Володимир Олексійович Магунь Андрій Ярославович Мякуш Оксана Романівна popup.nrat_date 2020-04-02 Close