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Information × Registration Number 0221U106437, 0121U114189 , R & D reports Title Controlling the Atomic Distribution for the Functionalization of the Hybrid Fe16N2-Martensite Phase Based Materials as an Alternative to Permanent Magnets Made of Rare Earth Intermetallics or Permendur popup.stage_title Head Radchenko Taras M., Доктор фізико-математичних наук Registration Date 07-12-2021 Organization Institute of Metal Physics. G.V. Kurdyumov of the National Academy of Sciences of Ukraine popup.description2 The features of varying the relative concentration of N atoms in the octahedral interstices of b.c.t. Fe, and therefore, the degree of its tetragonality are elucidated. We determined how the equilibrium concentration of residual vacancies relates with a concentration of thermally activated vacancies at the sites of impurity-free b.c.c. metal at the same temperature, and calculated the curve of the dependence of equilibrium concentration of residual site vacancies on the total content of interstitial N atoms. From the profile of the obtained curve, we estimated the values of the relative concentrations of interstitial N atoms, when (at a given temperature) a spontaneous transition of part of N atoms from the octahedral interstices to the b.c.t.-Fe sites actually occurs. The concentration value of possible transfer of nitrogen atoms to the b.c.t.-Fe-lattice sites at a fixed temperature is determined. Parameterizing interatomic interactions, the expressions with the explicit contribution of the exchange interaction of magnetic moments of metal ions in the expression for the mixing energy and implicit in the expression for the entropy of the magnetic subsystem are obtained. This made it possible to calculate the temperature dependences of the parameters of the atomic and magnetic (magnetization) orders at different values of the spin numbers of the “iron” subsystem. The presence of residual vacancies in the system at hand results in improving its magnetic properties through increasing the Courier temperature. Pressure (or deformation) can change the sign of the rate of change of the parameter of the atomic (magnetic) order; therefore, an alloy that is ordered (disordered) at zero (atmospheric) pressure may be disordered under the action of pressure or deformation. The decisive factor in the choice of the atomic redistribution scenario is the obvious “competition” of temperature and pressure or deformation as external influences. Product Description popup.authors Gatsenko Oleksandr S Lizunov Vyacheslav V. Tatarenko Valentyn А. popup.nrat_date 2021-12-07 Close