Microstructure analysis of hybrid aluminum parts from recycled EN AW-6082 and EN AW-7075 chips

Microstructure analysis of hybrid aluminum parts from recycled EN AW-6082 and EN AW-7075 chips

URSINUS Jonathan, KOCH Alexander, BRUNOTTE Kai, WALTHER Frank, BEHRENS Bernd-Arno

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Abstract. In order to promote aluminum scrap recycling and reduce remelting losses, solid-state recycling processes are subject to increasing academic attention. These processes range from severe plastic deformation (SPD) to diffusion-based processes like field-assisted sintering (FAST). In this study, a FAST-based recycling route consisting of precompaction, FAST, and impact extrusion of dry machined EN AW-6082 and EN AW-7075 aluminum chips was used to create multi-material parts from different aluminum alloys. To examine the effect on the resulting part quality, two different hybrid material layouts were created during cold compaction of the chips. The subsequent sintering process took place in a field-assisted sintering (FAST) machine at 400°C and 500°C for a duration of 5 min under a pressure of 85 MPa, allowing for the analysis of inter-chip diffusion. These sintered blanks were then cold-formed by impact extrusion. Metallographic and computed tomography analyses as well as hardness measurements were performed for property evaluation before and after heat-treatment.

Aluminum, Recycling, Chips, FAST, Extrusion, Hybrid Materials

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: URSINUS Jonathan, KOCH Alexander, BRUNOTTE Kai, WALTHER Frank, BEHRENS Bernd-Arno, Microstructure analysis of hybrid aluminum parts from recycled EN AW-6082 and EN AW-7075 chips, Materials Research Proceedings, Vol. 28, pp 1977-1986, 2023

DOI: https://doi.org/10.21741/9781644902479-213

The article was published as article 213 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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