2012 Volume 52 Issue 10 Pages 1902-1908
Development of a model for estimating the viscosity of a molten silicate is important because viscosity plays an important role in high-temperature processes. However, there is still much controversy with regard to the type of equation that is appropriate for expressing viscosity changes with changes in composition and temperature. In the present work, the composition dependence of viscosity for molten silicates in binary systems was investigated based on a double exponential function. The relationship between the double logarithm of viscosity, which is an inverse of a double exponential function, and the composition was clarified using the available experimental data. We found that the double logarithm of viscosity is linearly related to the composition in certain composition ranges. The double exponential function derived empirically by fitting it to the experimental data shows a reasonable viscosity dependence on composition and temperature. The linear relationship between the double logarithm of viscosity and the composition can be derived by assuming that the probability function of the occurrence of flow in a binary silicate melt has a Gumbel distribution.