Structure of the TiO2_MgO-Al2O3 system: Insights from molecular dynamics simulations

Molecular dynamics simulations were adopted to characterize the structure of the TiO2_MgO-Al2O3 system. The average bond lengths of Ti-O and Al-O keep unchanged and the average bond length of Mg-O increases from 1.98 angstrom to 2.01 angstrom, when the TiO2 content increases from 40% to 85%. The [TiO6] octahedron is dominating in all the [TiOn] polyhedra. Most of Ti-O-Ti bond angles keep unchanged at 101.25 degrees, while small part of Ti-O-Ti bond angles decrease from 127.68 degrees to 126.30 degrees, when the TiO2 content increases from 40% to 85%. The proportions of Ti-O-Ti oxygen connections increase from 16.58% to 65.80%, the proportions of Mg-O-Ti oxygen connections decrease from 36.24% to 5.44%, and the viscosity of the system increases from 0.042 Pa s to 0.118 Pa s, when the TiO2 content increases from 40% to 85%. This work will lay the foundation for predicting the viscosity of titanium slag melt, increasing the preparation efficiency of titanium slag, and improving the product quality of titanium slag.

Automated summary

Molecular dynamics simulations were used to study the structure of the TiO2_MgO-Al2O3 system. The bond lengths of Ti-O and Al-O remained unchanged, while the bond length of Mg-O increased with increasing TiO2 content. The [TiO6] octahedron was the dominant structure in the system. The majority of Ti-O-Ti bond angles remained unchanged, while a small portion decreased. Increasing TiO2 content resulted in an increase in the proportion of Ti-O-Ti oxygen connections and a decrease in the proportion of Mg-O-Ti oxygen connections, leading to an increase in viscosity.