Si Purity Control and Separation from Solidification of Al–30Si Melt under Pulse Electromagnetic Field

Abstract:

Purification of metallurgical-grade silicon (MG–Si) by a combination of Al-Si solidification refining and electromagnetic oscillating separation and acid leaching collection has been studied. The primary Si crystals and Al-Si alloy in hypereutectic Al-30%Si melt were separated during solidification under the pulse electromagnetic field (PEF). The results show that the Si content in Si-rich layer increases with increasing discharging frequency. The typical metallic impurities (Fe, Ti, and Ca) have removal fraction higher than 99.5%. The removal fractions of the impurities B and P which are more difficult to remove are over 90% and 85%, respectively.

• Periodical: Materials Science Forum (Volume 817)
• Pages: 379-384
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.817.379
• Online since: April 2015
• Authors: Qing Chuan Zou, Jin Chuan Jie, Jin Ling Sun, Ting Ju Li*
• Keywords: Pulse Electromagnetic Field, Purification, Separation, Solidification

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