Experimental and molecular dynamics examination of the interface interaction between magnesium oxide and magnetite in a high temperature oxidation environment

Abstract

The formation mechanism of sintering neck between magnesium oxide and magnetite under high temperature oxidation environment requires more investigation due to the limitations of high-temperature process monitoring techniques. Through a series of roasting experiments, this research quantitatively investigated the impact of MgO on the roasted microstructure and consolidation behavior of magnetite based on previous research. The results showed that with the increase of MgO content in pellets, the consolidation index of pellets decreased from 0.71 to 0.50, and the porosity increased from 7.24% to 13.57%. The existence of MgO could hinder the interface interaction, reduce the consolidation index and increase the porosity. Furthermore, molecular dynamics simulations were performed to investigate the crystal transformation and migration behavior from a molecular standpoint. The simulation findings revealed that the creation of the sintering neck was caused by atom migration and diffusion. Mg2SiO4 has minimal influence on the migration of the atoms, while MgO and MgFe2O4 have a large impact on pellet consolidation. This work gave new ideas for evaluating porous sintering materials, which may lead to additional research into the interface interaction between heterogeneous oxide during the sintering material formation process.

Keywords

• Iron ore pellets
• Crystal growth
• Consolidation index
• Atom migration
• Molecular dynamics