Factors affecting eutectic Si modification in Al-Si hypoeutectic alloy with the addition of Na, Sr, Eu and Yb

摘要

Factors affecting eutectic Si modification in Al-Si hypoeutectic alloy with the addition of Na, Sr, Eu and Yb were investigated. The modification effect is determined by element concentration in eutectic Si, which is mainly attributed to the solubility of modifying element M in alpha-Al and the interaction energy parameter of Al (or Si) and modifying element. A great modification is achieved by M of a limited solubility in alpha-Al and a moderate interaction energy parameter of Si (or Al) and M. The results are verified by the experimental results reported in the previous literatures. The effect of cooling rate on modification is also discussed in this work.