Viscosity and Structure Changes of CaO-SiO₂-Al₂O₃-CaF₂ Melts with Substituting Al₂O₃ for SiO₂

详细信息    查看全文

• 作者：Guo-hua ZHANG ^{ghzhang_ustb@163.com" class="auth_mail" title="E-mail the corresponding author}Author Vitae ; Yu-lan ZHEN ; Kuo-chih CHOU
• 关键词：high aluminum steel ; CaO-SiO2-Al2O3-CaF2 ; viscosity ; Raman spectrum ; mould flux
• 刊名：Journal of Iron and Steel Research, International
• 出版年：2016
• 出版时间：July 2016
• 年：2016
• 卷：23
• 期：7
• 页码：633-637
• 全文大小：286 K

文摘

During the smelting process of the high Al steels, the reaction between SiO₂ in molten slag and dissolved aluminum in liquid steel always takes place. This aluminathermic reduction reaction will lead to the substitution of 1 mol SiO₂ for 2/3 mol Al₂O₃. Therefore, the investigations about the influence of the ratio of Al₂O₃ to SiO₂ on viscosity and structure changes of mould flux during this process are very necessary. The viscosity variation of CaO-SiO₂-Al₂O₃-CaF₂ melts was studied by changing compositions considering the aluminathermic reduction reaction. It was found that viscosity increased monotonously with gradually increasing the substitution extent. According to the Raman analysis, the substitution of Al₂O₃ for SiO₂ leads to the decrease of non-bridging oxygen but the increase of bridging oxygen. Therefore, degree of polymerization and viscosity increase as the substitution extent increases. By comparing the measured viscosities with the model calculated values, it was found that both the recently developed Zhang's model and Roboud model could describe the viscosity variation behavior of CaO-SiO₂-Al₂O₃-CaF₂ melts very well.