Вплив ливарної форми і перегріву розплаву алюмінієвої бронзи на структуру виливків і якість їх поверхні

• Дата: 2023
• Автори: Солоненко, Людмила, Реп’ях, Сергій, Узлов, Костянтин, Мазорчук, Володимир
• Формат: Стаття
• Мова: Українська
• Опубліковано: Physico-technological Institute of Metals and Alloys 2023
• Теми: ливарна форма; структура; структурування; рідке скло; бронза; швидкість затвердіння; теплоізоляційна суміш
• Онлайн доступ: https://www.metalsandcasting.com/index.php/mcu/article/view/18
• Назва журналу: Metal and Casting of Ukraine

This work is devoted to regularities of sand-sodium-silicate mixture (SSSM) mold, structured in steam-microwave environment (steam-microwave solidification method – SMS-process), and copper melt with 9.4 % Al overheating influence revealing on castings structure and surface quality. In this investigation standard and generally accepted research methods and techniques have been used. Purpose of this work – influence regularities detection of mono-block and combined dry mixtures made and structured by SMS-process molds as well as castings melt overheating on products structure and their surface quality. Present research tasks have been determination of sodium silicate solute content and sand-sodium-silicate conglomerates SSSM size, aluminum bronze melt overheating temperature influence on castings structure, surface quality, solidification rate, and SSSM composition optimization due to sodium silicate solute content and its sand-sodium-silicate conglomerates size. It has been found that mixtures structured by SMS-process with 1.5 % sodium silicate solute and conglomerates sizes up to 0.315 mm, allow to produce copper and bronze castings without burns (sodium cuprate). At the same time, SSSM with conglomerates sizes up to 0.315 mm and more than 0.315 mm has been recommended to be used, respectively, as molding mixture for casting and as thermal insulation mixture for its gating system. With melt overheating increasing from 80 to 130 °С melt solidification time in molds, structured by SMS-process, increases. In this case, with overheating increasing, melt crystallization duration increases most intensively with overheating heat removal time from the melt slight increasing. Volumetric solidification rate dependence on sodium silicate solute content in SSSM in range from 0.5 to 2.5 % has an extremal character with maximum content of 1.5 % sodium silicate solute. Castings macrostructure with changes of sodium silicate solute content in SSSM practically does not change, but transforms from fine-crystalline to large-crystalline with melt during pouring overheating temperature increasing. Based on research results, recommendations for SSSM structured by SMS-process implementation in castings manufacturing have been developed.