Feasibility study of solid-state recycling through direct hot rolling of aa5754 aluminum chips for automotive applications

Recently, researchers have done a lot of efforts to develop new solid-state recycling processes, both experimentally and developing numerical models. This kind of process is energy saving and environmentally friendly compared to the conventional aluminum recycling process because it avoids the melting step. The purpose of this study is to assess the feasibility of an innovative solid-state recycling process using direct hot rolling in a non-heat-treatable aluminum alloy for automotive applications. The chips made of AA5754 have been produced by turning a bar without the usage of lubricants and compacted with a 150 kN load; the compacted billets were treated at 400°C and directly hot rolled in several successive passes. Rolled samples are then analyzed in terms of Vickers microhardness and microstructure in both as-rolled and heat treatment conditions, this last was performed at 185°C simulating the process of paint-bake. The produced sheets exhibit an excellent consolidation and bonding between chips.