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Information × Registration Number 0209U001867, 0106U004021 , R & D reports Title Influence of non-equilibrium defects on the kinetics of nanostructural transformations popup.stage_title Head Gusak Andriy Mikhailovich, Доктор фізико-математичних наук Registration Date 12-03-2009 Organization B. Khmelnitsky state university in Cherkasy popup.description2 Main results: (1) Theory and software for modeling of formation and collapse of hollow nanoshells. Peculiarities of competition between Frenkel, Kirkendall, inverse Kirkendall, Gibbs-Thomson effects are found. Void formation can be suppressed by capillary effect in too small particles. Phenomenological and Monte Carlo models are proposed, which self-consistently describe theformation as well as shrinkage of nanoshells. (2) Theory of spinodal decomposition with account of nonequilibrium vacancies. If diffusivities of components differe very significantly, then the most probable interlamellar spacing should be larger than that predicted by well-known Cahn-Hilliard theory. (3) Theory and software for modeling of coarsening stage of decomposition with account of limited efficiency of sinks and sources. At the intermediate stage of coarsening, when the mean istance between precipitates is less than the mean free path for vacancies, the growth law for mean size and the particle size distributions differ significantly from LSW predictions. (4) Theory and software for modeling of phase growth and competition under strong current via the contact zone of two metals. Account of reactions at interfaces is necessary. Nonequilibrium vacancies provide mechanism for partial compensation (damping) of external influence: if current assists the phase growth then nonequilibrium vacancies suppress it; if current suppresses phase growth then vacancies help it. (5) General thermodynamic criteria of predicting the evolution paths for multiphase systems. Criterion of maximal Gibbs free energy release rate was applied for 1) first phase to grow choice and second phase growth criterion at the example of NiSi system , 2) choice of optimal regime of interdiffusion at limited efficiency of vacancy sinks and sources, 3) interdiffusion in two-phase zones. (6) Theory and software for modeling of cellular precipitation and diffusion induced grainboundary migration with account of extremal principles. Product Description popup.authors popup.nrat_date 2020-04-02 Close