Forgeability characterization of multi-material based functionally graded materials manufactured through friction stir consolidation

Solid state recycling allows direct recycling of metal chips into semi-finished products. This process category proved to lower the environmental impact of metals recycling. Friction stir consolidation (FSC) is a new solid-state technique taking advantage of friction heat generation and severe plastic deformation to consolidate chips into billets. The new frontier of FSC process could be its evolution from recycling techniques towards the concept of upcycling technique: reuse (discarded objects or material) in such a way as to create a product of higher quality or value than the original. The authors have recently successfully applied FSC for producing multi-material based functionally graded materials (FGM). In this paper, the forgeability of the billet consolidated out of two dissimilar aluminium alloys AA 7075 and AA 2011-T3 chips, was analyzed. A proper forging test was designed, and mechanical and metallurgical properties of the forged parts were assessed through Vickers hardness measurements.