Experimental Study on the Segregation of Primary Silicon from the Hypereutectic Al-Si Melts in the Electromagnetic Directional Solidification

Abstract:

Solar grade silicon and modified Al-Si alloys are widely used in the world. These two favored materials are expected to obtain by the electromagnetic directional solidification of hypereutectic Al-Si melts. The segregation of hypereutectic Al-Si alloy is feasible with respect to the process of either pull-up or drop-down in electromagnetic directional solidification. To explore the segregation efficiency, experiments have been conducted in a high-frequency induction furnace with different pulling conditions of hypereutectic Al-Si melts. The results show that the segregation efficiency of dropping-down is higher than that of pulling-up; the slower dropping-down rate lead to higher segregation efficiency in the electromagnetic directional solidification; increasing the temperature gradient may promote the separation efficiency. A separation mechanism model responsible for the formation of the distribution of primary silicon in the cross-sections is also proposed. Wish to provide theoretical basis for the more efficiency of the segregation of hypereutectic Al-Si melts.

• Periodical: Materials Science Forum (Volumes 809-810)
• Pages: 363-368
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.809-810.363
• Online since: December 2014
• Authors: Hai Yang Xue, Guo Qiang Lv*, Wen Hui Ma, Xi Yang, Dao Tong Chen, Shao Yuan Li
• Keywords: Electromagnetic Directional Solidification, Hypereutectic Al-Si Melts, Segregation Efficiency, Separation Mechanism, Solar Grade Silicon

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