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Information × Registration Number 0208U000840, 0105U000977 , R & D reports Title The effect of the interatomic interaction on phase transformations in iron- and nickel-based solid solutions and their mechanical and functional properties popup.stage_title Head Gavriljuk Valentin Gennadievich, Доктор технічних наук Registration Date 20-02-2008 Organization Institute for metal physics NAS Ukkraine popup.description2 Correlation between electronic structure, thermodynamic stability of phases and both functional and mechanical properties of alloys on iron- and nickel-based alloys is investigated. It is shown that the alloying of fcc iron-based alloys by nitrogen+carbon essentially increases concentration of free electrons. It promotes metal character of interatomic bonds that leads to the raised thermodynamic stability of solid solution and creates prospect of working out economically alloyed corrosion-resistant high-strength austenitic steel. The optimum chemical composition of corrosion-resistant high-strength austenitic steel with record energy of shattering is developed and its properties are investigated. It is shown that fcc-hcp transformation induced by deformation plays an essential role in high coefficient of strain hardening. During this transformation plasticity raises and steel deformation proceeds. The role of alloying elements on fcc-hcp transformation caused by hydrogen in austenitic steels and mechanical properties hydrogen-charged steels is investigated. It is shown that the presence of epsilon-phase raises resistance to hydrogen embrittlement. Thus, hypothesis of hydrogen embrittlement according to which the epsilon-martensite is the reason of fragility is disproved. Evolution of electronic structure is investigated at martensitic and ferromagnetic transformation of alloys Ni-Mn-Ga. It is shown that at martensitic and ferromagnetic transformations there is no redistribution of charging density; however there is a reorganisation 3d bands to conditions of spin-up that of spin-down. As result, the magnetic moments on atoms of nickel and manganese are redistributed and the magnetic moment of an elementary cell increases. Influence of alloying on temperatures of phase (martensitic and magnetic) transformations ternary non-stochiometric Ni-Mn-Ga Heusler alloys is investigated. The alloyed 4-componental alloys Ni-Mn-Ga-(Cu, Fe) are created, that show reversible magneto-plastic deformations at a room temperature and above Product Description popup.authors popup.nrat_date 2020-04-02 Close