INTERACTION OF STRUCTURE AND PROPERTIES IN MODIFIED ALUMINUM ALLOYS
The effect of modification with dispersed compositions on the structure and mechanical properties of deformed aluminum alloys has been established. Aluminum alloys of the Al-Mg, Al-Mg-Sc systems have been investigated. A dispersed composition based on silicon carbide powder SiC with a particle size of 50 ... 100 nm was chosen as a modifier for the alloys under study. The dispersed modifier is obtained by plasma-chemical synthesis. The charge material was SiC powder with a dispersion of 50 μm. The mechanism of action of the dispersed modifier in the aluminum melt, which is the center of the primary crystallization of the melt, is proposed. The microstructure of the alloys was studied by the method of optical microscopy, and the phase composition was studied by the method of X-ray spectral energy dispersive analysis. The mechanical properties of the alloys before and after modification were carried out in accordance with GOST 1497-84. Industrial melting of AMg6, 1570, 1420 alloys was carried out. A technological process of melting was developed with an optimal amount of 0.2% modifier from the melt mass. The temperature-time parameters of the modification have been developed. The existence of complex intermetallic phases thia Al3(Scx, Zrx-1) in the modified state, which are effective solid solution hardeners, has been established. A significant increase in the mechanical properties of sheet alloys in a modified state is shown: ultimate strength - from 400 MPa to 470 MPa; yield point - from 280 MPa to 361 MPa; relative lengthening - from 13% to 15.4%. A significant decrease in the grain size in modified alloys by 1.5–2 times in comparison with unmodified ones has been established. A homogeneous microstructure with dispersed intermetallic phases located in the volume of grains was obtained. Fractographic analysis of the samples showed the presence of a brittle type of fracture in the initial state and ductile-brittle fracture of the samples in a modified state. The relationship of the grain structure of modified alloys with an increased complex of mechanical properties has been established. The results obtained made it possible to improve the technological process for the production of high-quality critical aluminum alloys.
Ищенко А. Я., Лабур Т. М. Сварка современных конструкций из алюминиевых сплавов: учебник. Киев, 2013. 405 с.
Кривов Г. А., Матвиенко В. А., Афанасьева Л. Ф. Мировая авиация на рубеже ХХ-ХХI столетий. Промышленные рынки: учебник. Киев : КВИЦ, 2015. 295 с.
Wemah K. Equipment for Aluminium Welding: Svetsdren, №2, 2016. Р. 11 – 13.
Jkura, N. Nagisawa, S. Iwata Technological developments for realizing aluminum bridges: Journal of Japan Institute of night Metals, №9, 2004. P. 380 – 387.
Мальцев М. В. Модифицирование структуры металлов и сплавов: М : Металлургия, 1994. 214 с.
Немененок Б. М. Теория и практика комплексного модифицирования силуминов: Л : Технопринт, 2016. 272 с.
Калинина Н.Е., Вилищук З.В., Калинин В.Т. Особенности модифицирования алюминиевых сплавов системы Al-Mg: Авиационно-космическая техника и технологи, №7 (84), 2016. С. 80-83.
Калинин В.Т., Дудников А.С., Качан А.Я., Калинина Н.Е. Получение нанокристаллических композиций управляемым плазмохимическим синтезом: Вестник двигателестроения. Запорожье: ЗНУ, №1, 2017. С. 86-90.