Life Cycle Assessment of aluminum alloys chips recycling through single and multi-step Friction Stir Consolidation processes

Manufacturing scientists have to find new processes enabling energy and resource efficient circular economy strategies. Solid state recycling processes have proved to be environmentally friendly alternatives to recycle aluminum alloys process scraps like chips. In this paper the environmental characterization of a solid state recycling process named Friction Stir Consolidation (FSC) is presented. A full Life Cycle Assessment (LCA) comparative analysis is developed: the environmental performance of new and different variants of FSC processes and remelting based routes are quantified and compared to one another. Also, different scenarios are analysed to provide guidelines for the correct implementation of FSC based recycling processes. Results revealed that: 1/ FSC is an environmentally friendly solution although a correct industrial implementation is needed to reduce non-productive production steps, 2/ the transition towards a wider use of renewable energy sources would amplify the advantage of FSC with respect to conventional remelting route in terms of environmental sustainability.