Abstract

CaF₂ has a significant effect on the viscosity of CaO-SiO₂ slags, which is closely related to the change of melts structure. In this study, molecular dynamics simulation has been used to study the influence of different adding methods of CaF₂ on the short-range and medium-range melt structure of CaO-SiO₂-CaF₂ at 1823 K. The results show that adding CaF₂ directly to the CaO-SiO₂ slags ((50-x/2)CaO-(50-x/2)SiO₂-xCaF₂, x = 5 ~ 20 mol%), the distribution of oxygen types and Qⁿ in the melt structure hardly change, indicating that the degree of polymerization (DOP) of the silicate network is not affected by this addition method. CaF₂ may reduce the viscosity of CaO-SiO₂ slags by diluting the network structure. However, using equimolar CaF₂ replaces CaO in CaO-SiO₂ slags ((50-x)CaO-50SiO₂-xCaF₂, x = 5 ~ 20 mol%), the oxygen type in the melt structure changes from non-bridging oxygen to bridging oxygen, and more Qⁿ species with high DOP appear, the overall DOP of network structure increases. If the viscosity of the CaO-SiO₂ slag is mainly controlled by the DOP of the melt structure, the viscosity of CaO-SiO₂ slags should be increased by this addition method.

Graphical Abstract

中文翻译：

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成分与结构的关系：通过分子动力学模拟不同添加CaF2方法对CaO-SiO2渣熔体结构的影响

摘要

CaF _{2对CaO-SiO 2}渣的黏度有显着影响，这与熔体结构的变化密切相关。本研究通过分子动力学模拟研究了CaF _{2的不同添加方式对CaO-SiO 2} -CaF ₂在1823 K时短程和中程熔体结构的影响。 ₂直接对CaO-SiO ₂渣((50- x /2)CaO-(50- x /2)SiO ₂ - x CaF ₂ , x  = 5~20 mol%), 分布氧的种类和Q ⁿ在熔体结构中几乎没有变化，表明硅酸盐网络的聚合度（DOP）不受这种添加方法的影响。CaF ₂可以通过稀释网络结构来降低CaO-SiO _{2渣的粘度。}但是，使用等摩尔量的CaF ₂代替CaO-SiO ₂渣中的CaO（(50- x )CaO-50SiO ₂ - x CaF ₂ , x  = 5 ~ 20 mol%），熔体结构中的氧类型从非桥接转变为氧转为桥接氧，出现更多高DOP的^Qn物种，网络结构的整体DOP增加。_{如果 CaO-SiO 2}的粘度渣主要受熔体结构的DOP控制，采用这种添加方法应提高CaO-SiO _{2渣的粘度。}

图形概要