Observation on the Formation of β-Al5FeSi Phase Depending on the Content of Fe in Aluminium Cast Alloy

This work examines the effect of different iron contents on the formation of the second iron phase group Al-Fe-Si: Al5FeSi in aluminium alloy. Specifically, it focuses on alloys containing iron at 0.123 wt. %, 0.454 wt. %, and 0.655 wt. %. The study investigates the variations in size and content of Al5FeSi, as well as their influence on the porosity formation and mechanical properties of AlSi7Mg0.3 cast alloys. One notable challenge presented by these phases is their detrimental effect on the mechanical and fracture properties of aluminium casts. With the increasing utilization of recycled metals, which typically contain higher iron levels, understanding the correlation between iron content and the resultant properties becomes critical. Observations employed various analytical techniques, including scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), and optical microscopy, along with quantitative analysis software. The results confirm the enlargement of β-needles phase particles and the increase in pore sizes correlated with higher iron content.