Siberian Federal University, Krasnoyarsk, Russia:

S. B. Sidelnikov, Professor, Chair for Metal Forming, Doctor of Technical Sciences, e-mail: sbs270359@yandex.ru
V. I. Ber, Associate Professor of the Chair for Metal Forming, Doctor of Technical Sciences, e-mail: kafomd_1@mail.ru
E. S. Lopatina, Associate Professor, Chair for Metal Science and Heat Treatment of Metals Named after V. S. Biront, Candidate of Technical Sciences, e-mail: eslopatina@mail.ru
M. V. Voroshilova, Postgraduate Student of the Chair for Metal Forming, e-mail: aniram1988@yandex.ru

The challenge of obtaining spherical thin-walled parts of large diameter with the same wall thickness from scandium-alloyed aluminum alloys of the Al-Mg system used in the rocket and space industry leads to the search for new technical and technological solutions. The article presents the results of research of the process of obtaining thin-walled spherical shells with a relative thickness A = (S/D)·100 ≤ 0.5 from a new alloy 1580 of the Al – Mg system economically alloyed with scandium. This alloy, despite the minimum (up to 0.1% (wt.)) content of scandium, which determines its low cost, can be easily processed by pressure. This makes it possible to manufacture deformed semi-finished products from it with an increased level of strength and plastic properties. At the first stage of research in laboratory conditions, the modes of rolling sheet semi-finished products from this alloy with a thickness of up to 2 mm were developed. For the production of pilot batches of flat products from largesized ingots of alloy 1580 under industrial conditions, the results of laboratory studies and computer simulation of the hot and cold rolling process were used. It has been established that the obtained experimental and industrial samples of sheet products have the necessary structure, which determines the high level of mechanical properties required for further cold deformation. For the manufacture of thin-walled spherical shells, a new drawing method has been developed, which provides for the preliminary operation of forming annular ribs. This ensures that, during subsequent drawing (due to deformation of the obtained ribs and final calibration), the manufacture of a part with the same thickness throughout the volume, and also reduces the number of transitions and heat treatment operations. To implement this method, dies have been developed and the sequence of operations for manufacturing spherical shells has been determined.
The work was carried out within the framework of the state task for science of the Siberian Federal University, project number FSRZ-2020-0013.

1. Romanovskiy V. P. Handbook of Cold Forging. 6^th edition, revised. and additional. Leningrad: Mashinostroenie, 1979. 520 p.
2. Yashin V. V., Aryshenskiy V. Yu., Latushkin I. А., Tepterev V. S. Substantiation of a manufacturing technology of flat rolled products from Al – Mg – Scbased alloys for the aerospace industry. Tsvetnye Metally. 2018. No. 7. pp. 75–82.
3. Yashin V. V., Aryshenskii E. V., Beglov E. D., Tepterev M. S., Grechnikova A. F. Development of a mathematical model of plate rolling on hot reversing mills. Key Engineering Materials. 2017. Vol. 746. pp. 48–55.
4. Orlov V. К., Drozd V. G., Sarafanov М. А. Features of rolling aluminum alloy plates. Proizvodstvo prokata. 2016. No. 4. pp. 11–16.
5. Bronz А. V., Efremov V. I., Plotnikov А. D., Chernyavskiy А. G. Alloy 1570C is a material for sealed structures of promising reusable articles of RSC Energia. Kosmicheskaya tekhnika i tekhnologii. 2014. No. 4. pp. 62–67.
6. Filatov Yu. А., Plotnikov А. D. Structure and properties of deformed semifinished products from aluminum alloy 01570C of the Al – Mg – Sc system for RSC Energia`s article. Tekhnologiya legkikh splavov. 2011. No. 2. pp. 15–26.
7. Yashin V. V., Rushchits S. V., Aryshenskiy E. V., Latushkin I. А. Rheological behavior of 01570 and AA5182 wrought aluminum alloys under hot deformation conditions. Tsvetnye Metally. 2019. No. 3. pp. 64–69.
8. Dovzhenko N. N., Rushchits S. V., Dovzhenko I. N., Yurev P. О. Understanding the behavior of aluminum alloy P-1580 sparingly doped with scandium under hot deformation. Tsvetnye Metally. 2019. No. 9. pp. 80–86.
9. GOST 4784–2019. Aluminium and wrought aluminium alloys. Grades. Introduced: 01.09.2019.
10. Mann V. Kh., Alabin A. N., Khromov A. P., Valchuk S. V. et al. Aluminum-based alloy. Patent RF, No. 2735846. Applied: 27.12.2019. Published: 09.11.2020. Bulletin No. 31.
11. Zakharov V. V. Prospects for creating alloys sparingly alloyed with scandium. MiTOM. 2018. No. 3. pp. 40–44.
12. Yashin V. V., Aryshenskiy E. V., Kolbasnikov N. G., Tepterev M. S., Latushkin I. А. Effect of microalloying with transition and rare earth metals of the aluminum-magnesium system on mechanical properties during thermomechanical treatment. Proizvodstvo prokata. 2017. No. 8. pp. 42–48.
13. Zakharov V. V., Filatov Yu. А., Fisenko I. А. Alloying of aluminum alloys with scandium. MiTOM. 2020. No. 8. pp. 31–36.
14. Zakharov V. V., Fisenko I. А. Some principles of alloying aluminum alloys with scandium and zirconium using ingot technology for the production of deformed semi-finished products. MiTOM. 2019. No. 4. pp. 14–19.
15. Zakharov V. V. Prospects of creation of aluminum alloys sparingly alloyed with scandium. Metal Science and Heat Treatment. 2018. Vol. 60. pp. 172–176.
16. Koryagin Yu. D., Ilin S. I. Peculiarities of recrystallization of wrought aluminum-magnesium alloys with scandium. Vestnik YUrGU. Seriya “Metallurgiya”. 2017. Vol. 17, No. 1. pp. 65–72.
17. Shi Ch., Zhang L., Wu G., Zhang X., Chen A. et al. Effects of Sc addition on the microstructure and mechanical properties of cast Al – 3 Li – 1.5 Cu – 0.15 Zr alloy. Materials Science & Engineering. 2017. Vol. А680. pp. 232–238.
18. Li M., Pan Q., Shi Y., Sun X., Xiang H. High strain rate superplasticity in an Al – Mg – Sc – Zr alloy processed via simple rolling. Materials Science & Engineering. 2017. Vol. А687. pp. 298–305.
19. Buranova Yu., Kulitskiy V., Peterlechner M., Mogucheva A., Kaibyshev R. et al. Al₃(Sc, Zr) - based precipitates in AlMg alloy: Effect of severe deformation. Acta Materialia. 2017. Vol. 124. pp. 210–224.
20. Pereiraa P. H. R., Wang Y. C., Huang Yi, Langdon T. G. Influence of grain size on the flow properties of an Al – Mg – Sc alloy over seven orders of magnitude of strain rate. Materials Science & Engineering. 2017. Vol. А685. pp. 367–376.
21. Mondol S., Alamb T., Banerjee R., Kumar S., Chattopadhyay K. Development of a high temperature high strength Al alloy by addition of small amounts of Sc and Mg to 2219 alloy. Materials Science & Engineering. 2017. Vol. А687. pp. 221–231.
22. Yashin V., Beglov E., Aryshensky E., Latushkin I. Large size metal-clad ingots rolling process analysis using finite elements method. Journal of Siberian Federal University. Engineering & Technologies. 2018. Vol. 11, No. 4. pp. 419–426.
23. Baranov V. N., Sidelnikov S. B., Frolov V. F., Zenkin E. Yu. et al. Investigation of mechanical properties of cold-rolled, annealed and welded semifinished products from the test alloys of Al – Mg system, economically alloyed with scandium. IOP Conf. Series: Materials Science and Engineering. 2018. Vol. 411. 012015.
24. Baranov V., Sidelnikov S., Voroshilov D., Yakivyuk O. et al. Study of strength properties of semi-finished products from economically alloyed highstrength aluminium-scandium alloys for application in automobile transport and shipbuilding. Open Engineering. 2018. Vol. 8, No. 1. pp. 69–76.
25. Sidelnikov S. B., Yakivyuk О. V., Baranov V. N., Zenkin E. Yu., Dovzhenko I. N. Development, modeling and research of technology for obtaining long deformed semi-finished products from aluminum-magnesium alloy with low scandium content. Izvestiya vuzov. Tsvetnaya metallurgiya. 2019. No. 6. pp. 51–59.
26. Mann V. Kh., Sidelnikov S. B., Konstantinov I. L., Baranov V. N. et al. Modeling and investigation of the process of hot rolling of large-sized ingots from aluminum alloy of the Al – Mg system, economically alloyed by scandium. Mater. Sci. Forum. 2019. Vol. 943. pp. 58–65.
27. Konstantinov I. L., Baranov V. N., Sidelnikov S. B., Zenkin E. Yu.,Yury ev  P. O. et al. Influence of rolling and annealing modes on the properties of sheet semi-finished products from wrought aluminum alloy 1580. Izvestiya
vuzov. Tsvetnaya metallurgiya. 2020. No. 5. pp. 63–69.
28. Konstantinov I. L., Baranov V. N., Sidelnikov S. B., Arnautov A. D. et al. Investigation of cold rolling modes of 1580 alloy by the method of computer simulation. The International Journal of Advanced Manufacturing Technology. 2021. Vol. 112. pp. 1965–1972.
29. Sidelnikov S., Dovzhenko I., Belokonova I. Simulation of process rolling plates from alloy of Al – Mg system economically doped with scandium. Solid State Phenomena Submitted. 2021. Vol. 316. pp. 509–514.
30. Mitin A. S., Mitin A. A. Method of thin-walled shells with bottom making. Patent RF, No. 2601364. Applied: 13.04.2015. Published: 10.11.2016. Bulletin No. 31.