Influence of Ni in high Fe containing recyclable Al-Si cast alloys

Research in recycling Al-alloy is necessary for a sustainable industrial development. Iron present in the recycled Al-alloys deteriorates its mechanical properties. The challenge, therefore, is to tackle the iron impurity using different methodologies. The present study focuses on a strategy by which iron containing beta phase could be destabilized with the addition of Ni. A large number of microstructural image, lattice parameter data and mechanical properties have been obtained using optical microscopy with state-of-the-art image analysis, FESEM with EDS and EBSD, XRD, Vickers microhardness and universal tensile testing. Based on these results, the present work provide necessary insight about the effect of Ni addition in the recycled Al-Si cast alloys containing as high as 2wt% Fe. Finally, it was concluded that up to 4wt% Ni addition could be beneficial for Al-Si alloys Si content limited to 9wt%. [Display omitted] •β-Al9Fe2Si2 phase exhibits solubility for Ni, where Ni occupies Fe sites.•Si can replace both Fe and Ni sites in Al9FeNi phase.•Ni destabilizes β-Al9Fe2Si2 phase and promotes Al9FeNi phase.•Destabilization of β-Al9Fe2Si2 phase due to Ni is more prominent when Si content is 4wt% deteriorates the mechanical properties of the alloys.