Arrhenius model for high-temperature glass-viscosity with a constant pre-exponential factor

A simplified form of the Arrhenius equation, ln η = A + B(x)/T, where η is the viscosity, T the temperature, x the composition vector, and A and B the Arrhenius coefficients, was fitted to glass-viscosity data for the processing temperature range (the range at which the viscosity is within 1-10³ Pa s) while setting A = constant and treating B(x) as a linear function of mass fractions of major components. Fitting the Arrhenius equation to over 550 viscosity data of commercial silicate glasses and approximately 1000 viscosity data of glasses for nuclear-waste glasses resulted in the A values of −11.35 and −11.48, respectively. The fraction of the variability (R²) value ranged from 0.92 to 0.99 for commercial glasses and was 0.98 for waste glasses. The Arrhenius models estimate viscosities for melts of commercial glasses containing 42-84 mass% SiO₂ within the temperature range of 1100-1550 °C and viscosity range of 5-400 Pa s and for waste glasses containing 32-60 mass% SiO₂ within the temperature range of 850-1450 °C and viscosity range of 0.4-250 Pa s.