Influence of preliminary heat treatment on structure and strength of high-strength aluminum alloy subjected to high pressure torsion with various strains

M.V. Markushev, E.V. Avtokratova, Y.L. Burdastykh, S.V. Krimsky, O.S. Sitdikov show affiliations and emails
Received 23 September 2020; Accepted 26 October 2020;
This paper is written in Russian
Citation: M.V. Markushev, E.V. Avtokratova, Y.L. Burdastykh, S.V. Krimsky, O.S. Sitdikov. Influence of preliminary heat treatment on structure and strength of high-strength aluminum alloy subjected to high pressure torsion with various strains. Lett. Mater., 2020, 10(4) 517-522


Nanoscale precipitates of aluminides of transition metals and the main strengthening phase are one of key factors controlling nanostructuring the Al alloy 1965 during SPD and its mechanical properties.Samples with diam. 20 mm and thickness 1.5 mm from a high-strength commercial aluminum alloy 1965 with uni- and bimodal size distributions of nanoscale precipitates of aluminides of transition metals, as well as the main strengthening phase, obtained under preliminary heat treatment, were subjected to high-pressure torsion (HPT) under pressure 6 GPa at room temperature. Number of revolutions was varied in the range from 0.5 to 10. Methods of transmission electron microscopy and X-ray diffraction analyses were used to certify initial structure-phase states of the alloy and also to investigate the kinetics and mechanisms of deformation structuring of its matrix. On the basis of the data on evolution of structure and hardness of the HPT processed samples, the nature and features of the alloy deformation hardening, depending on heterogeneity of initial structure and strain, were studied. Parameters of the alloy static strength under tension at room temperature were estimated. It was shown that the strain-induced formation of the well-developed nanocellular structure in the alloy matrix may be most effective in terms of its enhanced structural strength: at a rather high level of the alloy hardening obtained, its ductility remained also quite high. Activation of fragmentation and continuous dynamic recrystallization with formation of extremely dispersed nanofragmented and / or nanograined structures, resulted in increased brittleness of failure amid even more enhanced alloy strengthening, as well as to sharp decrease in its ductility, and, hence, in loss of its durability. The role of the dispersed phases and strain in formation of the phase-structural state, ensuring the best balance of the alloy mechanical properties, is discussed.

References (15)

1. R. Z. Valiev, R. K. Islamgaliev, I. V. Alexandrov. Progr. Mater. Sci. 45, 103 (2000). Crossref
2. T. G. Langdon. Acta Mater. 61, 7035 (2013). Crossref
3. Y. Estrin A. Vinogradov. Acta Mater. 61, 782 (2013). Crossref
4. R. R. Mulyukov, R. M. Imayev, A. A. Nazarov, M. F. Imayev, V. M. Imayev. Superplasticity of Ultrafine Grained Alloys: Experiment, Theory, Technologies. Nauka, Moscow (2014) 284 p. (in Russian) [Р. Р. Мулюков, Р. М. Имаев, А. А. Назаров, М. Ф. Имаев, В. М. Имаев. Сверхпластичность ультрамелкозернистых сплавов: эксперимент, теория, технологии. Наука, Москва (2014) 284 с.].
5. M. V. Markushev, E. V. Avtokratova, S. V. Krymskiy, O. Sh. Sitdikov. J. Alloys Compd. 743, 773 (2018). Crossref
6. M. V. Markushev, Y. L. Burdastykh, S. V. Krymskiy, O. S. Sitdikov. Lett. Mater. 7 (2), 101 (2017). Crossref
7. M. V. Markushev, E. V. Avtokratova, O. Sh. Sitdikov. Lett. Mater. 7 (4), 459 (2017). Crossref
8. P. J. Apps, M. Berta, P. B. Prangnell. Acta Mater. 53, 499 (2005). Crossref
9. N. A. Koneva, E. V. Kozlov. Tambov State Univer. Bull. 8 (4), 514 (2003). (in Russian) [Н. А. Конева, Э. В. Козлов. Вестн. Тамб, Гос. у-та. 8 (4), 514 (2003).].
10. O. S. Sitdikov. Lett. Mater. 5 (1), 74 (2015). (in Russian) [О. Ситдиков. Письма о материалах. 5 (1), 74 (2015).]. Crossref
11. T. Sakai, A. Belyakov, H. Miura. Metall. Mat. Trans. 39, 2206 (2008). Crossref
12. P. J. Hurley, F. J. Humphreys. Acta Mater. 51, 1087 (2003). Crossref
13. S. V. Krymskiy, D. K. Nikiforova, M. Yu. Murashkin, M. V. Markushev. Prosp. Mater. 12, 387 (2011). (in Russian) [С. В. Крымский, Д. К. Никифорова, М. Ю. Мурашкин, М. В. Маркушев. Перспективные материалы. 12, 387 (2011).].
14. O. Sitdikov, S. Krymskiy, M. Markushev, E. Avtokratova, T. Sakai. Rev. Adv. Mater. Sci. 31, 62 (2012).
15. V. I. Elagin, L. B. Ber, T. D. Rostova, E. I. Shvechkov, O. G. Ukolova. Techn. of Light Alloys. 2, 20 (2013). (in Russian) [В. И. Елагин, Л. Б. Бер, Т. Д. Ростова, Е. И. Швечков, О. Г. Уколова. Технология легких сплавов. 2, 20 (2013).].

Similar papers


1. Russian Science Foundation - 16-19-10152 P
2. basic researches of RAS - АААА-А19-119021390107-8