National Research Tomsk State University, Tomsk, Russia:

N. I. Kakhidze, Research Engineer, e-mail: kakhidze.n@yandex.ru
V. V. Platov, Junior Researcher
A. P. Khrustalev, Senior Researcher, Candidate of Physical and Mathematical Sciences
A. A. Akhmadieva, Undergraduate Student

Adoption of structural materials that combine high strength with low specific weight ensures a better energy efficiency of industrial machines and equipment. An aluminium part is almost three times lighter than its steel counterpart. However, it takes high-strength materials to replace critical components that are made of steel. There are high-strength aluminium alloys that contain scandium. However, they only find limited application because of high initial cost of scandium. Erbium works similarly to scandium in terms of strengthening of aluminium alloys, and its cost is 32 times lower. The problem of developing Al – Er alloys is of relevance today. At the same time, more study is necessary to understand the effect of erbium on the overall properties of aluminium alloys. The authors looked at the effect of erbium on the structure, mechanical properties and the fracture pattern of AMg5 alloy (Al – Mg system). Due to the melting temperature difference, erbium was introduced in the aluminium melt as part of an addition alloy produced by an advanced hydriding process. This paper describes a combined study into the obtained addition alloys and as-cast and as-deformed alloys. The authors examined the alloys following a classical pattern of materials research: i.e. composition – structure – properties. Special attention was given to understanding the structure. Thus, conventional optical techniques and scanning electron microscopy were applied, including energy dispersive analysis and electron backscattered diffraction technique. Following a uniaxial tensile test, a positive effect of erbium was observed on the strength of AMg5 alloy in the quasi-static loading region. The obtained results indicate that erbium can potentially be used as a doping element for aluminium alloys. Certain actions are proposed aimed at process optimization to maximize the strengthening effect of erbium in aluminium industry.
This research was funded by the Ministry of Education and Science of the Russian Federation under Governmental Assignment no. FSWM-2020-0028.
This research was carried out using the facilities of the Tomsk Regional Centre of Shared Knowledge at Tomsk State University and the funding by the Ministry of Science and Higher Education of the Russian Federation received under Contract No. 075–15-2021–693 (No. 13.ЦКП.21.0012) dated 26/07/2021.

1. Ciner C., Lucey B., Yarovaya L. Spillovers, integration and causality in LME nonferrous metal markets. Journal of Commodity Markets. 2020. Vol. 17. p. 100079.
2. Sun Y., Pan Q., Luo Y., Liu S., Wang W. et al. The effects of scandium heterogeneous distribution on the precipitation behavior of Al3 (Sc, Zr) in aluminum alloys. Materials Characterization. 2021. Vol. 174. p. 110971.
3. Zhang X., Wang H., Yan B., Zou C., Wei Z. The effect of grain refinement and precipitation strengthening induced by Sc or Er alloying on the mechanical properties of cast Al – Li – Cu – Mg alloys at elevated temperatures. Materials Science and Engineering: A. 2021. Vol. 822. p. 141641.
4. Hansen N. Hall–Petch relation and boundary strengthening. Scripta Materialia. 2004. Vol. 51, Iss. 8. pp. 801–806.
5. Zhang Z., Chen D. L. Contribution of Orowan strengthening effect in particulate-reinforced metal matrix nanocomposites. Materials Science and Engineering: A. 2008. Vol. 483. pp. 148–152.
6. Zakharov V. V. Effect of scandium on the structure and properties of aluminum alloys. Metal Science and Heat Treatment. 2003. Vol. 45, Iss. 7. pp. 246–253.
7. Migdissov A., Strzelecki A. C., Boukhalfa H., Sauer K. B., Nisbet H. D. et al. Selective hydrothermal extraction of lanthanides: mimicking natural oreforming processes. Los Alamos National Lab. 2020. Iss. LA-UR-20-21659.
8. Croteau J. R., Griffiths S., Rossell M. D., Leinenbach C., Kenel C. et al. Microstructure and mechanical properties of Al – Mg – Zr alloys processed by selective laser melting. Acta Materialia. 2018. Vol. 153. pp. 35–44.
9. Vazirov N. Sh., Ganiev I. N., Norova M. T., Maksudova M. S. Corrosion and electrochemical behavior of cerium-doped AMg6 alloy. News of the Academy of Sciences of the Republic of Tajikistan. Department of physical, mathematical, chemical, geological and technical sciences. 2013. No. 13. pp. 91–98.
10. Wu Z. G., Song M., He Y. H. Effects of Er on the microstructure and mechanical properties of an as-extruded Al – Mg alloy. Materials Science and Engineering: A. 2009. Vol. 504, Iss. 1-2. pp. 183–187.
11. Lin S., Nie Z., Huang H., Li B. Annealing behavior of a modified 5083 aluminum alloy. Materials & Design. 2010. Vol. 31, Iss. 3. pp. 1607–1612.
12. Nie Z. R., Li B. L., Wang W., Jin T. N., Huang H. et al. Study on the erbium strengthened aluminum alloy. Materials Science Forum. 2007. Vol. 546. pp. 623–628.
13. Wen S. P., Xing Z. B., Huang H., Li B. L., Wang W. et al. The effect of erbium on the microstructure and mechanical properties of Al – Mg – Mn – Zr alloy. Materials Science and Engineering: A. 2009. Vol. 516, Iss. 1-2. pp. 42–49.
14. Petrov I. A., Telitsyna O. V. Understanding the effect of certain rare earth elements on the properties of eutectic silumins. Tekhnologiya legkikh splavov. 2021. No. 1. pp. 54–59.

15. Wang S. H., Meng L. G., Yang S. J., Fang C. F., Hai H. A. O. et al. Microstructure of Al – Zn – Mg – Cu – Zr – 0.5 Er alloy under as-cast and homogenization conditions. Transactions of Nonferrous Metals Society of China. 2011. Vol. 21, Iss. 7. pp. 1449–1454.
16. Fang H. C., Chao H., Chen K. H. Effect of Zr, Er and Cr additions on microstructures and properties of Al – Zn – Mg – Cu alloys. Materials Science and Engineering: A. 2014. Vol. 610. pp. 10–16.
17. Karnesky R. A., Dunand D. C., Seidman D. N. Evolution of nanoscale precipitates in Al microalloyed with Sc and Er. Acta Materialia. 2009. Vol. 57, Iss. 14. pp. 4022–4031.
18. Belgibayeva A., Abzaev Y., Karakchieva N., Erkasov R., Sachkov V. et al. The structural and phase state of the TiAl system alloyed with rare-earth metals of the controlled composition synthesized by the “Hydride technology”. Metals. 2020. Vol. 10, Iss. 7. p. 859.
19. Vorozhtsov S., Minkov L., Dammer V., Khrustalyov A., Zhukov I. et al. Ex situ introduction and distribution of nonmetallic particles in aluminum melt: modeling and experiment. JOM. 2017. Vol. 69, Iss. 12. pp. 2653–2657.
20. Zaloga A. N., Dubinin P. S., Yakimov I. S., Bezrukova O. E., Burakov S. V. et al. Full-profile X-ray analysis based on Rietveld refinement, self-configuring multiple-population genetic algorithm and elemental analysis data. Zavodskaya laboratoriya. Diagnostika materialov. 2018. Vol. 84, No. 3. pp. 25–31.
21. ErAl3 mp-2134 Materials Explorer. Available at: https://materialsproject.org/materials/mp-2134 (Accessed: 18.02.2022).
22. Matsokin D. V., Pakhomova I. N., Matsokin V. P. Accumulation and relaxation of internal stresses during high-temperature creep of single crystals under impeded dislocation glide. Poroshkovaya metallurgiya. 2008. No. 11-12. pp. 27–35.
23. Filatov Yu. A. Further development of wrought aluminium alloys of the Al – Mg – Sc system. Tekhnologiya legkikh splavov. 2021. No. 2. pp. 12–22.
24. Dobatkin S., Estrin Y., Zakharov V., Rostova T. Y., Ukolova O. et al. Improvement in the strength and ductility of Al – Mg – Mn alloys with Zr and Sc additions by equal channel angular pressing. International Journal of Materials Research. 2009. Vol. 100, Iss. 12. pp. 1697–1704.
25. Lepov V. V., Lepova K. Ya., Alymov V. T., Larionov V. P. Stochastic modelling of a decomposing heterogeneous damageable medium. Fizicheskaya mezomekhanika. 2002. Vol. 5, No. 2. pp. 23–41.
26. Glezer A. M. A new approach to the description of structural phase transformations under extremely high plastic deformations. Izvestiya vysshikh uchebnykh zavedeniy. Fizika. 2008. Vol. 51, No. 5. pp. 36–46.