Effect of TiO₂ on the Viscosity and Slag Structure in Blast Furnace Type Slags

Abstract

Abstract TiO 2 additions up to 10 mass% behaved as a basic oxide and lowered the viscosity in the CaO–SiO 2 –17 mass% Al 2 O 3 –10 mass% MgO‐based slags by depolymerizing the silicate network structure. Raman spectroscopy revealed the sum of NBO/Si 1 and 3 decreased while the sum of NBO/Si 2 and 4 increased with TiO 2 content. Unlike the silicate structures, the aluminate structures seems to be relatively unaffected by TiO 2 additions according to the FTIR results. 5 mass% TiO 2 significantly decreased the viscosity compared to the TiO 2 free slags, but beyond 5 mass% TiO 2 meaningful changes in the viscosity was not observed. From the comparison of the viscosity at constant TiO 2 of 5 and 10 mass% and varying CaO/SiO 2 ratio, increasing the CaO/SiO 2 ratio was more effective in decreasing the viscosity than TiO 2 additions.