Achieving simultaneous improvement in strength and ductility in Al–Si–Mg–Ce alloy through synergistic morphology modification of eutectic (Si) and Al2Si2Ce phases by Sr addition

In this paper, it was found for the first time that with Sr addition in Al–Si–Mg–Ce alloy, the morphology of eutectic (Si) can be modified from branch to fine fibrous, while the bulk-like Al2Si2Ce phase may replace the elongated needle-like one. Moreover, Mg was observed to segregate along the (Al)/Al2Si2Ce interface and Sr was found to concentrate in the interior of Al2Si2Ce phase. Such heterostructured Sr–Al2Si2Ce was also supported by first-principles calculations. The synergistic morphology modification of eutectic (Si) and Al2Si2Ce phases by Sr addition stimulated the simultaneous improvement in strength and ductility in Al–Si–Mg–Ce alloy.