Strong and ductile recycled Al-7Si-3Cu-1Fe alloy: Controlling the morphology of quasicrystal approximant α-phase by Mn and V addition

This paper provides insights into microstructure control of recycled Al-7Si-3Cu alloy, which is widely used in the automotive industry. Here we report a detailed study of the Mn and V addition effects on the morphological modification of the quasicrystal approximant α-phase. We demonstrate that the addition of 0.3 wt% of V and 1.0 wt% of Mn to the Al-7Si-3Cu-1Fe alloy combined with the solidification features of spray-forming leads to the formation of a microstructure containing nano-submicron size quasicrystal approximant α-phase. Such microstructure results in an improved combination of strength and ductility up to 250 °C. Rotary swaging and Si globulization treatment performed as secondary processing leads to further improvement of the alloy’s tensile properties at different temperatures. The present work provides significant contributions on recycling of alloys without addition of primary Al and a prospect for more valuable applications.