Abstract
The global transition to a circular economy hinges on the development of sustainable recycling processes for end-of-life vehicles. Ongoing electrification and material choices over the recent decades hinder their integration in existing recycling pathways. This results in a large surplus of low-grade aluminium scraps and forfeits substantial energy, emissions, and cost savings, making the need for novel recycling approaches an urgent problem. This study presents a process for directly upcycling mixed end-of-life vehicles scrap into a high-performance aluminium alloy under realistic industrial conditions. It is compatible with existing infrastructure and dispenses the need for sorting, dilution or downcycling. By leveraging metallurgical principles and accelerated precipitation, the produced alloys achieve yield strengths that even surpass the commercial automotive alloy spectrum. This approach establishes a circular, low-emissions route to high-value aluminium recovery and offers a strategic model for transforming today´s and future´s critical raw material streams into next-generation structural alloys.
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Data availability
The raw data generated in this study have been deposited in the Zenodo repository under the accession code Doi: 10.5281/zenodo.1719276670.
Code availability
The python script for evaluating the diffusion enhancement upon pre-straining is also deposited in the Zenodo repository under the accession code Doi: 10.5281/zenodo.17192766 70.
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Acknowledgements
The work of P.K., P.D., M.A.T., T.K., S.S. and S.P. was funded/co-funded by the European Union (ERC, HETEROCIRCAL, 101124514, S.P.). Views and opinions expressed are, however, those of the author(s) only and do not necessarily reflect those of the European Union or the European Research Council. Neither the European Union nor the granting authority can be held responsible for them. The work of I.W., P.A. and B.T. was funded by the Christian Doppler Research Association within the framework of the Christian Doppler Laboratory for Deformation-Precipitation Interactions in Aluminium Alloys (I.W.) and the Christian Doppler Laboratory for Advanced Aluminium Alloys (S.P.). The financial support by the Austrian Federal Ministry of Labour and Economy, the National Foundation for Research, Technology and Development and the Christian Doppler Research Association is gratefully acknowledged. The research reported on here was supported by the Austrian Research Promotion Agency (FFG) in the context of projects 3DnanoAnalytics (FFG-No. 858040, S.P.) and Future Matter by APT (FFG-No. 884644, S.P.).
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P.K., P.A., I.W. and S.P. conceptualised the paper. P.K. was the leading research scientist, conducting material preparation, material processing, mechanical testing, sample preparation and writing the original draft. B.T. (EDX) and I.W. (EBSD and KAM) performed the SEM investigations. P.A. contributed to APT sample preparation, APT measurements and the interpretation of results. M.A.T. and T.K. performed the TEM measurements and interpreted the TEM results. P.D. wrote the Python script for the modelling of the yield strength. S.S. and P.K. illustrated the figures. S.P. supervised the research. All authors discussed and deliberated on the findings. All authors reviewed and approved the final version of the paper.
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Krall, P., Weißensteiner, I., Aster, P. et al. Direct aluminium-alloy upcycling from entire end-of life vehicles. Nat Commun (2026). https://doi.org/10.1038/s41467-026-69492-z
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DOI: https://doi.org/10.1038/s41467-026-69492-z
