Formation of a finely dispersed structure of secondary aluminum alloys by refining and correcting the chemical composition
DOI:
https://doi.org/10.15407/mom2025.04.024Keywords:
secondary aluminum alloys, aluminum recycling, flux refining, mechanical properties, 7xxx series alloysAbstract
This work is dedicated to developing a technological basis for optimizing the chemical composition, structure, and mechanical properties of secondary aluminum alloys obtained from the recycling of various types of aluminum scrap, including military and industrial origins. The relevance of this research is driven by the necessity for rational utilization of secondary raw materials, reduced energy consumption, and minimized environmental impact in the production of high-strength structural materials for the aviation and machine-building industries.
A remelting technology utilizing a binary NaCl-KCl salt flux system is proposed. This system ensures effective melt refining from non-metallic inclusions, intensifies degassing, and reduces the loss of alloying elements. An approach involving zinc (Zn) alloying is introduced to adjust the chemical composition of the secondary alloy, facilitating the formation of a high-strength Al-Zn-Mg system.
It is demonstrated that zinc alloying and additional flux treatment contribute to a reduction of harmful iron (Fe) impurities to 0.36-0.38%, a transformation in the morphology of iron-containing intermetallic phases, and a decrease in residual casting stresses. Metallographic and microstructural analyses confirmed the formation of a more homogeneous, fine-grained cast structure with a reduced defect density. The mechanical properties of the alloy in the as-cast state were determined: an ultimate tensile strength of 140 MPa and an elongation of 5.42%, which corresponds to an intermediate stage of property development prior to subsequent heat treatment.
The results confirm the potential of the developed technology as an effective foundation for producing secondary high-strength aluminum alloys with predictable structural and mechanical properties, suitable for practical application in critical structural components for aviation and general machine-building.
References
Hnatush, V. A. (2020). World trends of the market of secondary processing of waste and scrap of aluminum alloys. Casting Processes, (3), 56–69 [in Ukrainian].
Cappuzzi, S., & Timelli, G. (2018). Preparation and melting of scrap in aluminum recycling: A review. Metals, 8, 249.
Ashkenazi, D. (2019). How aluminum changed the world: A metallurgical revolution through technological and cultural perspectives. Technological Forecasting and Social Change, 143, 101–113.
Grand View Research. (2021). Aluminum market size, share & trends analysis report by processing method, by product form, by application … and segment forecasts, 2021–2028 (Report ID: GVR-1-68038-531-9).
Feister, T. (2018). Failure predictions in warm forming of 7075-T6 aluminum structural parts. IOP Conference Series: Materials Science and Engineering, 418, 012024.
European Aluminium Association. (2018). Aluminium in cars: Unlocking the light-weighting potential (24 p.). Brussels: EAA.
DriveAluminum. (2022). Roadmap for automotive aluminum.
Jiang, G. H., Xu, L., & Liu, H. T. (2020). Trends in aluminium alloy development and their joining methods. Materials Science Forum, 913, 3–15.
Kargarzadeh, A., Bamberger, M., & Brosh, E. (2022). Advanced casting methods for aluminum alloys: A review. Material Science and Engineering International Journal, 2(3).
Zolotorevsky, V. S., Belov, N. A., & Glazoff, M. V. (2018). Casting aluminum alloys (2nd ed., 544 p.). Elsevier Science.
Zolotorevsky, V. S., Belov, N. A., & Glazoff, M. V. (2007). Casting aluminum alloys (544 p.). Elsevier Science.
Mondolfo, L. F. (2021). Aluminum alloys: Structure and properties (971 p.). Butterworth-Heinemann.
Milani, V., & Timelli, G. (2025). Laboratory-scale procedure for evaluating the flux efficiency on melt cleanliness and tensile properties of recycled aluminum alloys. Advanced Engineering Materials. https://doi.org/10.1002/adem.202500824
Krivonosova, Ye. A., Gorchakov, A. I., & Scherbakov, Yu. V. (2014). Structure and properties of coatings in microarc oxidation. Welding International, 28(10), 816–819.
Kulikov, B., Partyko, E., Kosovich, A., Yuryev, P., Mansurov, Y., Stepanenko, N., Baykovskiy, Y., Bozhko, D., Durnopyanov, A., & Dombrovskiy, N. (2025). Analysis of composition, properties, and usage efficiency of different commercial salt fluxes for aluminum alloy refining. Metals, 15, 448. https://doi.org/10.3390/met15040448
Fiocchi, J., Colombo, C., Vergani, L. M., Fabrizi, A., Timelli, G., Tuissi, A., & Biffi, C. A. (2021). Heat treatments for stress relieving AlSi9Cu3 alloy produced by laser powder bed fusion. Materials, 14, 4184. https://doi.org/10.3390/ma14154184
Verkhovliuk, A. M. (2020). Influence of technological factors on the properties of a high-strength aluminum alloy of the Al-Zn-Mg-Cu system. Metal Science and Heat Treatment, (1), 27–36 [in Ukrainian].
Murat, Y., & Atılgan, İ. (2021). Aluminum alloys as advanced materials: A short communication. Research & Development in Material Science, 15(1), 1612–1615.
Fan, X., Gao, Z., & Hou, J. (2018). Nanostructured aluminum alloys: Processing, characterization and properties. Materials & Design, 140, 39–51.
Rajan, T. P. D., Pillai, R. M., & Pai, B. C. (2019). Reinforcement coatings and interfaces in aluminium metal matrix composites. Journal of Materials Science, 33, 3491–3503.
Wang, Y., et al. (2024). Effect of multi-element synergistic addition on the microstructure evolution and performance enhancement of laser cladded Al–Mg–Zn–(Mn–Cu–Er–Zr) alloy. Materials Science and Engineering A, 896, 146256.
Shin, S.-S., Lim, K.-M., & Park, I.-M. (2017). Effects of high Zn content on the microstructure and mechanical properties of Al–Zn–Cu gravity-cast alloys. Materials Science and Engineering A, 679, 340–349.
Sivasankaran, S., Rajendran, N., Balasubramanian, M., & Senthilnathan, N. (2021). Microstructural evolutions and enhanced mechanical performance of novel Al–Zn die-casting alloys processed by squeezing and hot extrusion. Journal of Materials Processing Technology, 292, 117063.
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Copyright (c) 2025 S. V. Petrychenko, V. V. Kovalenko, E. G. Byba, А. V. Minitskyi, I. V. Lukianenko, N. V. Minitska, М. М. Yamshinskij, M. Yu. Barabash
This work is licensed under a Creative Commons Attribution 4.0 International License.
