Chemical and Metallurgical Institute named after Zh. Abishev (Karaganda, Kazakhstan):

A. A. Akberdin, Dr. Eng., Prof., Head of the Bor laboratory
A. S. Kim, Dr. Eng., Chief Researcher of the Bor laboratory
A. S. Orlov, Dr. Eng., Senior Researcher of the Bor laboratory, e-mail: wolftailer@mail.ru
R. B. Sultangaziev, Dr. Eng., Senior Researcher of the Bor laboratory

The diagram of the phase composition of the Fe – Si – Al system and its isothermal sections within the temperature range of 300-3000 K are plotted. Thermodynamic data of Fe₃Si, Fe₂Si, Fe₅Si₃, FeSi, FeSi₂ silicides, FeAl, FeAl₂, FeAl₃, Fe₂Al₅ aluminides and Al₂Fe₂Si, Al₃FeSi, Al₂FeSi, Al₁₁Fe₃Si₆, Al₁₄Fe₃Si₃ ternary compounds are used. The diagram consists of 20 elementary triangles of coexisting phases, the number of which decreases to 6 at the temperature 1900 K and more. At the temperatures above 2900 K, the equilibrium of the condensed phases is disturbed due to the transition of such metal components of the low-melting aluminum corner of the diagram as Al, Al₂, Fe, Si and Si₂, leading to losses of valuable elements, to the gas phase. Crystallization fields are assessed by calculating the squares of elementary triangles, as well as the prevalence of each compound in the phase space by taking into account its participation in the construction of adjacent triangles. Using our own method, the mathematical model of the diagram was created in the form of equations for dependence of the amount of the formed phase on the chemical composition of examined metal. The computer program was developed based on the established equations. The examples of calculation of the phase composition of two grades of ferrosilicon FeSi65 and FeSi75, which are the most common in metallurgy, as well as two grades of ferrosilicoaluminum FeSi45Al15 and FeSi55Al20 are presented. Correspondence of the calculated and instrumentally found phase composition of the industrial metal has been revealed. Presence of mathematical models makes it possible to accelerate selection of the metal with the required composition and properties from the set of planned for smelting.

This research is funded by the Science Committee of the Ministry of Education and Science of the Republic of Kazakhstan (Grant No. AP09259368).

1. Khurmetbek Zh., Karbaev M., Akberdin A. A. Production of ferrosilicon with low aluminium content. The input of youth science in Kazakhstan-2050 strategy realization: Proceedings of the Republican student scientific conference. Part 2. Karaganda. 2016. 398 p.
2. Baisanov S., Tolymbekov M., Takenov T., Chekimbaev A. Development and mastering of the technology of ferrosilicoaluminium production. Physical-chemical and technological problems of metallurgical production in Kazakhstan. Collection of works. Chemical-metallurgical institute named after Zh. Abishev. Almaty. Iskander. 2002. Vol. 1. pp. 41-53.
3. Ovcharuk A. N., Taran A. Yu., Rudenko V. K. Ferrosilicoaluminium melting from secondary materials of abrasive production. Metallurgicheskaya i gornorudnaya promyshlennost. 2010. No. 3. pp. 37-41.
4. Udovichenko Yu. P., Onishchenko A. A. Parenchuk I. V., Parenchuk V. V. Ferroaluminium as a new ferroalloy for the iron and steel industry. Energosnabzhenie. 2004. No. 8. pp. 12-16.

5. Tomida S., Nakata K. Fe-Al composite layers on aluminum alloy formed by laser surface alloy iron powder. Surface and Coatings Technology. 2003. Vol. 174-175. No. 1. pp. 559-563.
6. Godlewska E., Szczepanik S., Mania R., Krawiarzand J., Koziñski S. FeAl materials from intermetallic powders. Intermetallics. 2003. Vol. 11. No. 4. pp. 307-312.
7. Seliverstov I. A., Trotsan G. N., Smirnov I. V. Study of structure and properties of Fe – Al based plasma coatings. Naukoviy visnik Khersonskoy derzhavnoy morskoy akademii. 2014. Vol. 10. No. 1. pp. 249-254.
8. Moiseev G. K., Ilyinykh N. I., Kulikova T. V. Thermodynamic researches of Al – Si system melts taking into account existence of “small” clusters. 1. Interval 1000-1600 K. Rasplavy. 2005. No. 4. pp. 27-33.
9. Isagulov A. Z., Baisanov S. O., Baisanov A. S., Azotte A., Shabanov E. Zh. Analytical expressions of Fe – Al – Si – Cr system and phase composition of alumosilicochromium complex alloy. Trudy universiteta. 2016. Vol. 63. No. 2. pp. 18-22.
10. Mondolfo L. F. Structure and properties of aluminium alloys. Moscow: Metallurgiya. 1979. 639 p.
11. Bannykh O. A. Phase composition diagrams for binary and multi-component Fe-based systems. Moscow: Metallurgiya. 1986. 224 p.
12. Dinsdale A. T. SGTE data for pure elements. Calphad. 1991. Vol. 15. pp. 317–425.
13. Akberdin A. A. Balance method for calculation of phase composition in multi-component systems. Kompleksnoe ispolzovanie mineralnogo syrya. 1995. No. 3. pp. 92-93.
14. Udalov Yu. P. Use of software complexes of calculating and geometric thermodynamics in designing of technological processes for inorganic substances. A manual. St. Petersburg. St. Petersburg state technological institute (Technical university). 2012. 147 p.
15. Tyushnyakov S. N., Selivanov E. N. Thermodynamic simulation of phase forming during cooling of zinc-bearing copper-melting slag. Butlerovskie chteniya. 2015. Vol. 43. No. 9., pp. 102-107.
16. Berezhnoy A. S. Multi-component systems of oxides. Kiev. Naukova dumka. 1970. 572 p.
17. Ilyinykh N. I., Moiseev G. K., Kulikova T. V., Shunyaev K. Yu., Leontyev L. I., Lisin V. L. Thermodynamic parameters of Fe – Al melts. Izvestiya Chelyabinskogo nauchnogo tsentra. 2003. Vol. 19. Iss. 2. pp. 32-36.
18. Zubov V. L., Gasik M. I. Ferrosilicon electrometallurgy. Dnepropetrovsk. Systemnye tekhnologii. 2002. 704 p.