TY - JOUR

T1 - Innovative Solid-State Recycling of Aluminum Alloy AA6063 Chips Through Direct Hot Rolling Process

AU - Carta, Mauro

AU - Ben Khalifa, Noomane

AU - Buonadonna, Pasquale

AU - El Mohtadi, Rayane

AU - Bertolino, Filippo

AU - El Mehtedi, Mohamad

PY - 2024/12/17

Y1 - 2024/12/17

N2 - In this paper, the feasibility of an innovative solid-state recycling process for aluminumalloy AA6063 chips through direct rolling is studied, with the aim of offering an environmentallysustainable alternative to conventional recycling processes. Aluminum chips, produced by millingan AA6063 billet without the use of lubricants, were first compacted using a hydraulic press witha 200 kN load and subsequently heat-treated at 570 ◦C for 6 h. The compacted chips were directlyhot-rolled through several successive passes at 490 ◦C. The bulk material underwent the same rollingschedule to allow comparison of the samples and assess the process, in terms of mechanical propertiesand microstructure. All the rolled samples were tested by tensile and microhardness tests, whereasthe microstructure was observed by an optical microscope and the EBSD-SEM technique. The fracturesurface of all tested samples was analyzed by SEM. Recycled samples exhibited good mechanicalproperties, comparable to those of the bulk material. In particular, the bulk material showed anultimate tensile strength of 218 MPa, in contrast to 177 MPa for the recycled chips, and comparableelongation at break. This study demonstrates that direct rolling of compacted aluminum chips is bothtechnically feasible and has environmental benefits, offering a promising approach for sustainablealuminum recycling in industrial applications within a circular economy framework.

AB - In this paper, the feasibility of an innovative solid-state recycling process for aluminumalloy AA6063 chips through direct rolling is studied, with the aim of offering an environmentallysustainable alternative to conventional recycling processes. Aluminum chips, produced by millingan AA6063 billet without the use of lubricants, were first compacted using a hydraulic press witha 200 kN load and subsequently heat-treated at 570 ◦C for 6 h. The compacted chips were directlyhot-rolled through several successive passes at 490 ◦C. The bulk material underwent the same rollingschedule to allow comparison of the samples and assess the process, in terms of mechanical propertiesand microstructure. All the rolled samples were tested by tensile and microhardness tests, whereasthe microstructure was observed by an optical microscope and the EBSD-SEM technique. The fracturesurface of all tested samples was analyzed by SEM. Recycled samples exhibited good mechanicalproperties, comparable to those of the bulk material. In particular, the bulk material showed anultimate tensile strength of 218 MPa, in contrast to 177 MPa for the recycled chips, and comparableelongation at break. This study demonstrates that direct rolling of compacted aluminum chips is bothtechnically feasible and has environmental benefits, offering a promising approach for sustainablealuminum recycling in industrial applications within a circular economy framework.

KW - Engineering

UR - https://www.mdpi.com/2075-4701/14/12/1442

M3 - Journal articles

VL - 14 (12)

JO - Metals

JF - Metals

SN - 2075-4701

IS - 1442

ER -