Abstract The distributions and morphologies of precipitates in metallurgical grade silicon (MG-Si) were investigated and effects to control solidification rate and electromagnetic strengthening were tested. Decreasing the solidification rate caused the inclusions to become larger, and electromagnetic strengthening enriched precipitates in the center of the melt. Additionally, acid etching of different samples using an HCl–HF mixed leaching agent revealed the evolution of the microstructure of inclusions in silicon. Corrosion results indicate that the HCl–HF mixture is an effective leaching agent that can be used to dissolve impurities in MG-Si. Using this reagent, the total impurity content of the source silicon was reduced from 6320 ppmw to 171.8 ppmw, and the impurity content after controlling the solidification rate or electromagnetic strengthening was reduced to 158.1 ppmw and 99 ppmw, respectively.

中文翻译：

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电磁强化冶金级硅中杂质的浸出行为

摘要 研究了冶金级硅（MG-Si）中析出物的分布和形貌，并测试了控制凝固速率和电磁强化的效果。降低凝固速度导致夹杂物变大，电磁强化在熔体中心富集析出物。此外，使用 HCl-HF 混合浸出剂对不同样品进行酸蚀刻，揭示了硅中夹杂物微观结构的演变。腐蚀结果表明 HCl-HF 混合物是一种有效的浸出剂，可用于溶解 MG-Si 中的杂质。使用该试剂，源硅的总杂质含量从 6320 ppmw 降低到 171.8 ppmw，