Transformation of Fe-rich intermetallic phases and eutectic Si morphology in Al–Si–Cu–Fe cast alloy with solution treatment

Abstract

The transformation of Al5FeSi intermetallic phase and eutectic Si morphology were studied with different solution treatment time at 510 °C. The results show that solution treatment can change the morphology of the acicular Fe phase and the eutectic silicon. As the solution time increases, the acicular Fe-rich phase and eutectic silicon gradually spheroidize, and the Fe-rich phase changes from Al5FeSi to Al8Fe2Si phase. When the solid solution time is 10 h, the ultimate tensile strength and elongation are 275.6 MPa and 3.5%, respectively. The fracture mode changes from quasi-cleavage fracture to ductile fracture after solution treatment, and a large number of dimples appear in the fracture morphology.