Effects of Basicity on the Oxidation Induration and Metallurgical Properties of Fluxed Pellets Prepared From High‐Silica Vanadium–Titanium Magnetite

Increasing the pellet proportion in blast furnace burdens is an effective approach to reducing sinter consumption and pollutant emissions. In this study, fluxed pellets were prepared from high‐silica vanadium–titanium magnetite concentrate, and the effects of basicity ( R = 0.33–1.20) on oxidation induration and metallurgical properties were investigated at 1225and 1250 °C. X‐ray diffraction, scanning electron microscope–energy‐dispersive spectroscopy, and thermodynamic equilibrium calculations were used to reveal phase evolution, microstructural changes, and liquid formation. The results show that pellet strength varied significantly with basicity. The highest compressive strength of 5013 N/pellet was obtained at R = 0.33 and 1250 °C, mainly due to hematite recrystallization and solid‐state sintering. Increasing basicity promoted Ca‐bearing silicate bonding phase formation and changed the bonding structure. As R increased from 0.33 to 1.20, the reducibility index (RI) increased from 81.77% to 92.27%, while the reduction swelling index (RSI) first increased to 18.63% at R = 0.80 and then decreased. The softening–melting interval decreased to 252 °C at R = 1.20. Overall, R = 1.20 and 1250 °C provided a suitable balance of metallurgical properties.