As part of the development of a novel and clean smelting process for the comprehensive utilization of Hongge vanadium titanomagnetite (HVTM), the objective of this study was to investigate the influence of MgO on the oxidation and induration of HVTM pellets (HVTMP). The results showed that the oxidation degree and compressive strength decreased significantly with the increase in added MgO, which corresponded to the increase in porosity. MgO reacted with Fe2O3 to form Mg–Fe solid solution. The evolution in microstructure was explained by the interactions between MgO and Fe2O3 at the grain boundaries. Mg2+ diffusion affected the oxidation and induration, and cracks were formed, resulting in the uneven distribution of grains and the inhibition of hematite recrystallization. Furthermore, the grain size decreased significantly. Based on the results, we proposed a diagram to describe the mechanism, which showed that MgO had a negative effect on the oxidation and induration of HVTMP.
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