Microstructure and Mechanical Properties of Al–12.6Si Eutectic Alloy Modified with Al–5Ti Master Alloy

The Al–12.6Si eutectic alloy has been modified via the Al–5Ti master alloy to improve both microstructure and mechanical properties. The results show that the fraction of the primary α–Al phase in the Al–12.6Si alloy and the mechanical properties of the resulting alloy vary considerably after modification with the Al–5Ti master alloy at different temperatures. With increasing modification temperature, the fraction of primary α–Al in the Al–12.6Si alloy increases, varying with the amount of added Al–5Ti. For an added amount of 0.2 wt.% Al–5Ti, the fraction of primary α–Al in the Al–12.6Si alloy reaches a maximum. The tensile strength and elongation of an Al–12.6Si alloy modified with 0.2 wt.% Al–5Ti at different temperatures evidently increase compare with unmodified alloys.