This study investigates the effect of highly fluorinated electroslag with TiO2 content of 0%, 3%, 6% and 9% on the melting process, crystallisation kinetics and crystalline product structure by using STA, XRD and SEM-EDS techniques. The results demonstrated a gradual decrease in the melting temperature, heat of fusion and first crystallisation temperature of the slag as the TiO2 content increased. The main precipitation phases in the slag are Ca12Al14O32F2, CaF2, CaZrO3, CaTiO3, (Ca, Zr, Ti)O2 and MgO. The larger the ratio of TiO2:ZrO2, the higher the precipitation rate of multi-faceted CaTiO3. The precipitation of dendritic CaZrO3 was also gradually suppressed. Crystallisation kinetic analysis revealed that the slag exhibited the highest activation energy for crystallisation at a TiO2 content of 6%. These findings have a positive impact on determining the TiO2 content in the electroslag and enhancing the surface quality of the ingot.
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