摘要
To separate primary Si from Si-Al-Sn alloy, directional solidification method was applied in this study. The effects and mechanisms of the cooling rate, alloy composition, and G/R ratio on bulk Si growth were investigated for optimizing parameters. By using of the constitutional supercooling criterion for single-phase growth from melts, the effects of Sn addition have been explored as compared with Si-Al and Si-Sn alloys. Finally, with the application of electron probe micro analyzer, the microstructure of Si and the distribution of Al and Sn were analyzed. Based on the obtained results, the directional solidification method is verified to be an effective method to separate Si from Si-Al-Sn alloy without any metal inclusions. The contents of Al and Sn in bulk Si are almost equivalent to the corresponding solid solubility. The obtained results indicate that directional solidification method can be an appropriate and effective technique to separate Si from alloy.