Effect of CeO2 on the viscosity and structure of high-temperature melt of the CaO-SiO2(-Al2O3)-CeO2 system.

• The viscosity was proportional to the CeO 2 content and the CeO 2 /Al 2 O 3 ratio. • CeO 2 made the structure of the silicon oxide ionic group to be simple. • The viscosity of the melt was influenced by the combination of Ce4+ and Ce3+. The effect of the CeO 2 content and CeO 2 /Al 2 O 3 ratio on the melt viscosity of CaO-SiO 2 (-Al 2 O 3)-CeO 2 was determined using the rotating cylinder method. The structural characteristics of the quenched vitreous samples were investigated with a Raman spectrometer. The results showed that the melt viscosity of CaO-SiO 2 (-Al 2 O 3)-CeO 2 decreased significantly with increases in the CeO 2 content and the CeO 2 /Al 2 O 3 ratio. Q 3/ Q 2, which represents the degree of polymerization of the melt, decreased with an increase in the CeO 2 content and the CeO 2 /Al 2 O 3 ratio. Ce in the CaO-SiO 2 (-Al 2 O 3)-CeO 2 system was present as a mixture of Ce4+ and Ce3+ in high-purity Ar atmosphere at a temperature of 1540 °C. In the CaO-SiO 2 (-6%Al 2 O 3)-6%CeO 2 system, the melt viscosity was higher in the presence of Ce4+ and Ce3+ than in the presence of Ce3+, indicating that the melt viscosity of CaO-SiO 2 (-Al 2 O 3)-CeO 2 was determined by the combination of Ce4+ and Ce3+. CeO 2 acted as a network modifier in the melt. [ABSTRACT FROM AUTHOR]