Papers by Vladimir Lebedev
Vestnik Udmurtskogo Universiteta. Matematika. Mekhanika. Komp'yuternye Nauki, 2014
Вестник Удмуртского университета, 2008
Вестник Удмуртского университета, 2012
Вестник Удмуртского университета, 2005
Вестник Удмуртского университета, 2008
Journal of Experimental and Theoretical Physics, Jul 1, 2019
A nonisothertmal model of spinodal decomposition is proposed for a binary system described by the... more A nonisothertmal model of spinodal decomposition is proposed for a binary system described by the Ginzburg-Landau energy. The initial stages of spinodal decomposition are investigated for a system of simultaneous equations describing the impurity and temperature redistribution. The dispersion equation and the instability growth rate of spinodal structures are obtained. The temperature dependence of the growth rate and the wave number corresponding to the maximum instability is found. The observed difference in the dispersion relations of isothermal and nonisothermal models shows that a criterion for the effect of temperature fluctuations on the spinodal decomposition is given by a dimensionless parameter Γ; for large values of Γ (Γ ≥ 1000), temperature fluctuations in the form of noise are certainly insufficient for spinodal decomposition due to a change in the dispersion structure of the equations, which suggests the need to take into account the nonisothermal behavior of the system.
Russian Metallurgy, Aug 1, 2016
A phase-field model is proposed for the solidification and melting of a binary concentrated solut... more A phase-field model is proposed for the solidification and melting of a binary concentrated solution (melt). The method of extended irreversible thermodynamics is used to derive thermodynamically consistent equations and to take into account low and high phase transformation rates. The Hillert parallel construction is applied to determine the driving forces of the solidification or melting of a binary system. When thermodynamic equilibrium states are described, the Gibbs potentials are assumed to be known. They are specified from the existing thermodynamic information databases or from experimental data. The results of a numerical investigation of the proposed model are presented.
Вестник Удмуртского университета, 2010
Вестник Удмуртского университета, 2007
Вестник Удмуртского университета, 2006
Журнал технической физики, 2022
The problems of constructing a multiphase model of the phase field for the processes of phase tra... more The problems of constructing a multiphase model of the phase field for the processes of phase transitions of the first kind are considered. Based on the Gibbs energy of the complete system expressed in terms of antisymmetrized combinations of phase fields, it is shown that the equations of dissipative dynamics of a locally nonequilibrium system follow from the condition of its monotonic decrease, preserving the normalization of the sum of variables by one and the following properties of the previously known two-phase model. Keywords: multiphase systems, phase transformations, locally nonequilibrium processes, dissipative systems with constraints.
Вестник Удмуртского университета, 2010
Regular & Chaotic Dynamics, 1998
Вестник Удмуртского университета, 2008
Вестник Удмуртского университета, 2012
Вестник Удмуртского университета, 2009
Computational Materials Science, Feb 1, 2019
Analysis of phase separation under non-isothermal conditions in undercooled molten Co-Cu droplets... more Analysis of phase separation under non-isothermal conditions in undercooled molten Co-Cu droplets has been performed theoretically. The calculated microstructure length scales agree with the Cahn-Hilliard (CH) and Langer-Baron Miller (LBM) models, and experimental data. At moderate cooling rates V 10 10 c 2
Physics of Metals and Metallography, Oct 1, 2013
Technical Physics, Apr 1, 2017
The temperature dependence of the interface mobility in the directed solidification of pure nicke... more The temperature dependence of the interface mobility in the directed solidification of pure nickel has been obtained in a locally nonequilibrium phase-field model using optimization based on the results of modeling a plane interface by the method of molecular dynamics. Thermodynamic calculations of motive forces and solidification heat-release process are based on the real Gibbs potentials for nickel.
Uploads
Papers by Vladimir Lebedev