Yield stress and work hardening behavior of extruded AA6082 profiles under different homogenization and extrusion conditions

Yield stress and work hardening behavior of extruded AA6082 profiles under different homogenization and extrusion conditions

WILLIAMS William M., SANDNES Lise, MA Jun, TRONVOLL Sigmund Arntsønn, WELO Torgeir

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Abstract. The mechanical properties of extruded AlMgSi alloys are affected by the applied thermo-mechanical parameters employed during the entire production process. In the following, the effect of different extrusion speeds and homogenization conditions paired with either air or water quenching, is examined on four different sets of rectangular hollow AA6082-T4 profiles. These profiles were fabricated and extruded under industrial conditions and selected cross sections of each profile were examined by optical microscopy to determine the microstructure and level of recrystallization. Uniaxial tension testing was used to explore the effect of homogenization conditions and extrusion cooling rate on mechanical properties. Tensile tests showed that the water-quenched extrusions had a higher yield and ultimate strength compared to air-quenched extrusions. Moreover, samples that had a recrystallized microstructure typically showed a larger standard deviation of mechanical properties, which may lead to product quality and consistency issues for metal forming operations. Overall, the present work provides a more in-depth understanding of how the selected thermo-mechanical parameters affect the resulting properties of such profiles. This can further contribute to expanding the potential for effective accommodation of extrusion parameters for zero-defect products.

Aluminum Extrusion, Thermo-Mechanical History, Work Hardening

Published online 4/19/2023, 10 pages
Copyright © 2023 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: WILLIAMS William M., SANDNES Lise, MA Jun, TRONVOLL Sigmund Arntsønn, WELO Torgeir, Yield stress and work hardening behavior of extruded AA6082 profiles under different homogenization and extrusion conditions, Materials Research Proceedings, Vol. 28, pp 467-476, 2023

DOI: https://doi.org/10.21741/9781644902479-51

The article was published as article 51 of the book Material Forming

Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

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