Influence of TiO₂ on the melting property and viscosity of Cr-containing high-Ti melting slag

Abstract

A study on the melting and viscosity properties of the chromium-containing high-titanium melting slag (CaO-SiO₂-MgO-Al₂O₃-TiO₂-Cr₂O₃) with TiO₂ contents ranging from 38.63wt% to 42.63wt% was conducted. The melting properties were investigated with a melting-point apparatus, and viscosity was measured using the rotating cylinder method. The FactSage 7.1 software and X-ray diffraction, in combination with scanning electron microscopy-energy-dispersive spectroscopy (SEM-EDS), were used to characterize the phase equilibrium and microstructure of chromium-containing high-titanium melting slags. The results indicated that an increase in the TiO₂ content led to a decrease in the viscosity of the chromium-containing high-titanium melting slag. In addition, the softening temperature, hemispheric temperature, and flowing temperature decreased with increasing TiO₂ content. The amount of crystallized anosovite and sphene phases gradually increased with increasing TiO₂ content, whereas the amount of perovskite phase decreased. SEM observations revealed that the distribution of the anosovite phase was dominantly influenced by TiO₂.

Keywords

titanium dioxide / Cr-containing high-titanium melting slag / melting property / viscosity / vanadium titanomagnetite

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