The effects of CaO and FeO on the structure and properties of aluminosilicate system: A molecular dynamics study

Using molecular dynamics simulations, the effects of different levels of calcium oxide and ferrous oxide on the local structural order, bonding network, transport characteristics, and other microstructures and viscosity of the aluminosilicate slag system were analyzed. It was found that CaO and FeO have almost no effect on the short-term ordering of aluminosilicates in the studied composition range. However, as the metal oxide content increases, the degree of depolymerization of CaO on the aluminosilicate network structure is greater than that of FeO. It shows that the degree of polymerization of calcium aluminosilicate system is lower than that of iron aluminosilicate, and the corresponding viscosity of this system decreases with the increase of metal oxide contents. When the mass fractions of CaO and FeO increase, the diffusion ability of each atom in the SiO2-Al2O3-CaO system is larger than that in the SiO2-Al2O3-FeO system. This indicates that the polymerization structure of SiO2-Al2O3-CaO slag system tends to be more simplified compared with SiO2-Al2O3-FeO system. (C) 2020 Elsevier B.V. All rights reserved.