Microstructural Characterization in Metallurgical Grade Silicon after Treatment by CaO-SiO₂ and Na₂O-SiO₂ Slags

Abstract:

The microstructure and impurities distribution in metallurgical grade silicon with treated by CaO-SiO₂ and Na₂O-SiO₂ slags were investigated. An exhaustive analysis of the transformation of precipitated phase at grain boundaries has been carried out. Prior to slag treatment, Si-Fe system intermetallic was the primary precipitated phase in metalllurgical grade silicon. After treated by CaO-SiO₂ slag, Si-Ca system intermetallic became the main precipitated phase, such as Si-Ca, Si-Ca-Ti, Si-Ca-Al and Si-Fe-Ca. But Na₂O-SiO₂ slag had another result on refining metallurgical grade silicon; only Si-Fe-Ti phase was generated in precipitated phase and the low level of sodium in treated silicon was obtained.

• Periodical: Advanced Materials Research (Volume 815)
• Pages: 404-408
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.815.404
• Online since: October 2013
• Authors: Ming Fang, Cheng Hao Lu, Liu Qing Huang, Hui Xian Lai, Juan Chen, Jin Tang Li, Wen Hui Ma, Jian Ning Shen, Zhi Lin Sheng, Xue Tao Luo
• Keywords: Impurity, Metallurgical Grade Silicon, Microstructure, Precipitated Phase, Slag

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