Solidification behavior, microstructure and mechanical properties of Al-(1 to 5)Fe-1V-1Si alloys

The paper deals with solidification behavior, microstructure and mechanical properties of the untreated and Ni-Mg treated Al-(1–5)Fe-1Si-1V cast alloys. The alloys are prepared by melting in a clay bonded graphite crucible in a resistance heating furnace and cast in a permanent mould. In both unmodified and modified alloys, the solidification proceeds through several invariant reactions indicating different phase formation at different temperatures. The structure mainly consists of Al₃Fe type precipitates and silicides phases. The morphology and size of the precipitates changed after Ni-Mg alloy modification treatment. The first invariant reaction temperature increases with increasing Fe content and also with modification treatment. The tensile strength of the alloys increased considerably with increase in Fe content but at the expense of ductility. Modification treatment further improves the mechanical properties.