ВПЛИВ МАСОВОГО СПІВВІДНОШЕННЯ АРМУЮЧОГО ЕЛЕМЕНТА ТА МАТРИЧНОГО СПЛАВУ НА ФОРМУВАННЯ ГЕТЕРОГЕННОГО ВИЛИВКА: Procesi littâ, 2023, Vol 3 (153), 25-33

• Дата: 2023
• Автори: Тарасевич, М.І., Шинський, О.Й., Шалевська, І.А., Корнієць, І.В.
• Формат: Стаття
• Мова: Ukrainian
• Опубліковано: National Academy of Sciences of Ukraine, Physical-Technological Institute of Metals and Alloys of NAS of Ukraine 2023
• Теми: армований виливок; процес теплопередачі; математичне та комп’ютерне моделювання
• Онлайн доступ: https://plit-periodical.org.ua/index.php/plit/article/view/205
• Назва журналу: Casting Processes

To obtain of castings with special functional properties, metal alloys are reinforced by necessary components in the liquid phase state. To solve an important technological problem when combining the components of a reinforced system regarding formation reliable connection at the boundary "reinforcing element - matrix alloy" in the article, the change in the thermal state of the reinforced casting depending on the mass ratio of reinforcing elements and matrix alloy, which was varied from 10% to 50%, was investigated using mathematical and computer modeling methods. A cylindrical casting made of 35L steel with a diameter of 100 mm and a height of 200 mm, reinforced with cylindrical metal elements made of 20L steel with a diameter of 10 mm, was chosen as the object of the study. The initial temperature of the reinforcing elements was 20 °C; the pouring temperature of the matrix alloy was 1600 °C. The computational experiment was performed using a representative volume that corresponds to the studied casting. The thermophysical features of the interaction of the liquid and solid phases during the formation of a heterogeneous casting with the appropriate mass ratio of the components have been established. Based on the results of a computational experiment, the article provides graphical dependences of the temperature changes of the reinforcing element and metal during the formation of the casting and the thickness of the layer of metal that has frozen on the reinforcing element, when its volume fraction changes. The analysis of change of temperature of the liquid metal and the reinforcing element showed that the heat flow is sent to the heating of the reinforcing element. After a certain time a temperature is established in the "reinforcing phase — liquid metal" system, the value of which depends on the percentage of the reinforcing phase content. A series of computational experiments made it possible to establish that with a reinforcing phase content of up to 13 percent, the surface of the reinforcing element reaches the solidus temperature of the liquid metal in 2.25 seconds. Thus, the reinforcing element is in a two-phase state, and the reinforcing phase accelerated the heat and mass exchange processes and was not fixed as a reinforcing element in the casting. A reliable diffusion connection with the matrix alloy is ensured at a reinforcement content of 18% to 31.5%, while the surface of the reinforcing element acts as the center of crystallization. Increasing the reinforcing metal phase by more than 32 percent during gravity pouring of metal is impractical, because then the conditions for the effective connection of the reinforcing and liquid phase in the solidification process will not be provided. The obtained results can be used in the production of castings with special functional properties.