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Information × Registration Number 0211U006884, 0109U006378 , R & D reports Title Interphase boundaries during phase separation in bulk metallic glasses: theory and experiment. popup.stage_title Head Bakai Olexander Stepanovich, Доктор фізико-математичних наук Registration Date 12-05-2011 Organization National Science Center "Kharkiv Institute of Physics and Technology popup.description2 The subject of investigation is the structure of interphase boundaries in bulk metallic glasses. In order to clarify fundamental laws of interface boundaries formation at liquid-solid phase transitions concomitant to the growth of bulk amorphous alloys, the theoretical methods of statistical physics of condensed matter and physics of phase transitions (and, particularly, the methods of the heterophase state theory) are used. The proposed fluctuon model of a heterophase liquid has been applied to the description of the process of its solidification to both crystalline and amorphous states of solid. For various solidification conditions, the free energy functionals of the heterophase state of a fluid have been obtained and its equilibrium equations have been solved. It has been shown for the first time that the fluctuon model is capable of description of the pretransitional phenomena of liquid-solid crystallization both by the first order phase transition and in the possible case of a continuous "liquid-crystal" transformation. The condition has been established under which crystalline fluctuons make a small contribution to the free energy of a system at the "liquid-glass" or "glass-liquid" transformations. For these transformations, it has been shown that, on the one hand, the first order phase transition can occur when the solidification process is qualitatively similar to crystallization. On the other hand, the continuous solidification glass-forming process can take place. The temperature dependencies of thermodynamic quantities have been found for a continuous process of glass transition. The expression for the order-parameter fluctuations has been obtained, which gives a correct description both in the supercritical region and near the critical point in mean-field approximation. It has been shown that the developed non-crystalline heterophase fluctuations can significantly inhibit the crystallization rate of the supercooled heterophase liquid. It opens the door to a manageable process of the formation of crystal-amorphous solids. Product Description popup.authors Бакай Олександр Степанович Дюльдя Сергій Володимирович Лазарєв Микола Петрович popup.nrat_date 2020-04-02 Close