Derivation of the temperature dependent constants for KAIO2 and NaAIO2 in a viscosity predictive model for high aluminosilicate melts

Abstract

The compositional dependence of the viscosity was studied for two high aluminosilicate melt series: Na2O-CaO-Al2O3-SiO2 (NCAS) and K2O-Na2O-CaO-Al2O3-SiO2 (KNCAS). The viscosity and the glass transition temperature were measured by concentric cylinder viscometry and differential scanning calorimetry, respectively. This work discusses the viscosity predictive model set up by Bottinga and Weill. The temperature dependent constant, D, defining the relative impact of each component on the viscosity, was derived for the compositional range from 35 to 45 mol% SiO2 for KAIO2 and NaAlO2, respectively. With the newly derived D-values, a good agreement was achieved between measured and predicted values.