Friction stir consolidation of aluminium chips: A new approach to overcome the inhomogeneous properties of the consolidated billet

Friction stir consolidation of aluminium chips: A new approach to overcome the inhomogeneous properties of the consolidated billet

Riccardo Puleo, Giuseppe Ingarao, Livan Fratini

Abstract. The need to improve the recycling process of metals to achieve sustainability goals is reflected in the growing interest in solid-state recycling approaches. One of these is the Friction Stir Consolidation (FSC), able to directly transform chips into consolidated billets. The main features of this process are the pressure and the rotational speed of the tool which compresses and heats up the chips collected inside a designed die. During the consolidation process, the friction between the tool and chips surfaces plays an important role because it is the main source of heat, therefore the heat transfer starts near the tool to the bottom of the billet resulting in an inhomogeneous material property. This aspect leads to both inhomogeneous microstructure and hardness characterization of the consolidated billet. To improve the effectiveness of the friction stir consolidation recycling process, this study focused on a numerical approach by proposing a new setup in which the structure where the die and the chips are placed on, namely backing plate, was heated up aiming to activate a heat flow also from the bottom.

Keywords
Friction Stir Consolidation, Recycling, Aluminium, Chips

Published online 5/7/2025, 8 pages
Copyright © 2025 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: Riccardo Puleo, Giuseppe Ingarao, Livan Fratini, Friction stir consolidation of aluminium chips: A new approach to overcome the inhomogeneous properties of the consolidated billet, Materials Research Proceedings, Vol. 54, pp 2447-2454, 2025

DOI: https://doi.org/10.21741/9781644903599-264

The article was published as article 264 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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