ISIJ International ( IF 1.8 ) Pub Date : 2020-10-20 , DOI: 10.2355/isijinternational.isijint-2020-002 Xiaobo Zhang 1, 2 , Chengjun Liu 1, 2 , Maofa Jiang 1, 2
The melt structure with fluorine addition has been investigated using molecular dynamics (MD) simulation for the CaO–SiO2–CaF2 and CaO–Al2O3–CaF2 ternary slag system. By analyzing the coordination number of the network framework, the results indicate that the structure of Si–O tetrahedron is more stable than the structure of Al–O tetrahedron. F− ions are dominantly coordinated with Ca2+, there is a dynamic equilibrium between Ca2+ and the coordination anions (O2− and F−) in both systems, and the total coordination number (CN) is maintained between 6 and 7. The analysis of the distribution of oxygen types demonstrates the degree of polymerization (DOP) of network structure in CaO–SiO2–CaF2 system is lower than that in CaO–Al2O3–CaF2 system. Although the addition of CaF2 can lower the viscosity of both slag systems, the microscopic reasons for that are completely different: in CaO–SiO2–CaF2 system, CaF2 actually acts as network diluent, and creates the space where particles can move longer. But in CaO–Al2O3–CaF2 system, CaF2 can depolymerize the network structure of the melt.
中文翻译:
分子动力学模拟研究氟对CaO-SiO2-CaF2和CaO-Al2O3-CaF2熔体结构的影响
已经使用分子动力学(MD)模拟了CaO–SiO 2 –CaF 2和CaO–Al 2 O 3 –CaF 2三元渣系统的熔体结构。通过分析网络框架的配位数,结果表明Si–O四面体的结构比Al–O四面体的结构更稳定。˚F -离子显性用Ca协调2+,存在的Ca之间的动态平衡2+(和络阴离子Ò 2-和F -),两个系统的总配位数(CN)保持在6到7之间。氧类型分布的分析表明,CaO–SiO 2 –CaF 2系统中网络结构的聚合度(DOP)较低比CaO–Al 2 O 3 –CaF 2系统中的要高。尽管添加CaF 2可以降低两种炉渣系统的粘度,但微观原因是完全不同的:在CaO–SiO 2 –CaF 2系统中,CaF 2实际上充当网络稀释剂,并创造了颗粒可以移动的空间更长。但是在CaO–Al 2 O 3 –CaF中2体系中,CaF 2可以使熔体的网络结构解聚。