Дослідження фазових перетворень при кристалізації алюмінієвих сплавів методом гартувально-мікроструктурного аналізу: Processy litʹâ, 2020, Tom 141, №3, p.27-41

• Дата: 2020
• Автори: Пригунова, А. Г., Бєлік, В. І., Шеневідько, Л. К., Кошелєв, М. В.
• Формат: Стаття
• Мова: Ukrainian
• Опубліковано: National Academy of Sciences of Ukraine, Physical-Technological Institute of Metals and Alloys of NAS of Ukraine 2020
• Теми: алюміній-кремнієві сплави; кристалізація; фазові перетворення; гартування; швидкість охолодження
• Онлайн доступ: https://plit-periodical.org.ua/index.php/plit/article/view/91
• Назва журналу: Casting Processes

Received 15.06.2020 UDC 669.715:536.46:539.24/.27 The study of the mechanism of phase transformations during the formation of the structure of metals and alloys is a promising direction for improving the known and developing new materials. This makes it necessary to expand the methodological and experimental capabilities of their research. Widely used methods of metallographic analysis provide information on the structural features of alloys. At the same time, to determine the mechanism of phase formation by the microstructure of fully hardened samples is very problematic. The main tools for analyzing and predicting the structure when the temperature and composition of the alloys change are phase equilibrium diagrams. However, they cannot be applicable to the description of the kinetics of phase transitions. The work considers the methodological features of the developed quenching-microstructural analysis method, which allows one to study the stages and nature of phase transformations during crystallization, regardless of the degree of system metastability. It is based on high-speed hardening from phase transition temperatures determined by the DTA method. For the first time it was experimentally established that cooling rates corresponding to (1.8 - 3.7) × 103 0С / s, which are realized using the “stop-hardening” method, suppress or significantly limit the diffusion redistribution of elements during cooling. This allows you to effectively use the proposed analysis method to study the features of phase transformations during crystallization due to changes in the chemical composition, the influence of various external factors, in particular, the processing of the melt by electric current.