Actual Problems in Machine Building 2021 Vol.8 N1-2

Актуальные проблемы в машиностроении. Том 8. № 1-2. 2021 Материаловедение в машиностроении ____________________________________________________________________ 83 18. Influence of the thermal route on the peak-aged microstructures in an Al–Mg–Si aluminum alloy / S. Pogatscher, H. Antrekowitsch, H. Leitner et al. // Scripta Materialia. – 2013. – Vol. 68, iss. 2. – P. 158–161. – DOI: 10.1016/j.scriptamat.2012.10.006. 19. Natural ageing clustering under different quenching conditions in an Al–Mg–Si alloy / Z. Yang, X. Jiang, X. Zhang [et al.] // Scripta Materialia. – 2021. – Vol. 190. – P. 179–182. – DOI: 10.1016/j.scriptamat.2020.08.046. 20. The aging mode for reducing the thermal expansion of the piston from alloy AK21 / A.N. Prudnikov, V.A. Prudnikov, M.V. Popova et al. // IOP Conference Series: Materials Science and Engineering. – 2018. – Vol. 411, iss. 1. – P. 012060. – DOI: 10.1088/1757-899X/411/1/012060. 21. Ultrafast artificial aging of Al–Mg–Si alloys / M. Werinos, H. Antrekowitsch, E. Kozeschnik et al. // Scripta Materialia. – 2016. – Vol. 112. – P. 148–151. – DOI: 10.1016/j.scriptamat.2015.09.037. 22. Захаров В.В., Фисенко И.А. Влияние гомогенизации на структуру и свойства сплава системы Al–Zn–Mg–Sc–Zr // Металловедение и термическая обработка. – 2018. – № 6. – С. 12–17. 23. Постников Н.С. Упрочнение алюминиевых сплавов и отливок. – М.: Металлургия, 1983. – 119 с. 24. ГОСТ 1583–93. Сплавы алюминиевые литейные. Технические условия / Донецкий государственный институт цветных металлов. – Введ. 1997-01-01. – М.: Изд-во стандартов, 2003. – 24 с. IMPROVEMENT OF THE HEAT TREATMENT OF PISTON ALUMINUM ALLOYS Afanasyev V.K. D.Sc. (Engineering), Professor, e-mail: in_afanaseva@mail.ru Prudnikov A.N. , D.Sc. (Engineering), Professor, e-mail: a.prudnikov@mail.ru Popova M.V., D.Sc. (Engineering), Professor, e-mail: m.popova@rdtc.ru Prudnikov V.A. , Ph.D. student, e-mail: vladpr88@gmail.com Siberian State Industrial University, 42 Kirova st. Novokuznetsk, 654007, Russian Federation Abstract Methods for improving the modes of heat treatment of aluminum casting and wrought piston alloys of the Al-Si-Cu system are presented. For the aging of piston workpieces made of AK12, AK12MMгН alloys, a medium with an increased content of nitrogen and hydrogen was used - a vapor of an aqueous solution of carbamide CO(NH 2 ) 2 . It is shown that such processing allows to reduce the values of the temperature coefficient of linear expansion (TCLE) in the entire range of the studied temperatures (50-450 °C) by 3-20 % in comparison with the treatment mode recommended by GOST. Moreover, the duration of aging in such an environment is 3 hours instead of 12-16 hours according to standard modes. For pistons made of wrought alloys such as AK, AB and casting silumins AK5M2, AK5M7, a heat treatment method has been developed, including quenching, electrolytic hydrogenation and aging. Electrolytic hydrogenation of pistons before aging reduces its time by 2-6 times. In addition, hydrogenation makes it possible to reduce the aging temperature by 35-65 °C with a simultaneous or some increase in the strength (by 2-11 %) of alloys in comparison with standard processing modes. Keywords: alloy, silumin, piston, aging, temperature coefficient of linear expansion, electrolytic hydrogenation.