Study of Si/Al Ratio and Modification of Silicon Morphology in ZA27 Alloys

Changes in the primary Si phase in Al-Si alloys were analyzed and compared to the Si phase in ZA27 alloys with the same Si/Al ratio. The Si phase in the Al-Si alloys was modified and applied to ZA27 alloys to refine the Si phase of the microstructure. The results showed that the change in the ZA27 alloys was the same as that in the Al-Si alloys while good modification effects were obtained with a 1.5% Cu-P inter-alloy using two different processes.