Thermal Expansion Calculation of Silicate Glasses at 210 o C, Based on the Systematic Analysis of Global Databases

Abstract: Thermal expansion data for more than 5500 compositions of silicate glasses were analyzed statistically. These data were gathered from the scientific literature, summarized in SciGlass ® 6.5. The analysis resulted in a data reduction from 5500 glasses to a core of 900, where the majority of the published values is located within commercial glass composition ranges and obtained over the temperature range 20 to 500oC. A multiple regression model for the linear thermal expansivity at 210oC, including error formula and detailed application limits, was developed based on those 900 core data from over 100 publications. The accuracy of the model predictions is improved about twice compared to previous work because systematic errors from certain laboratories were investigated and corrected. The standard model error was 0.37 ppm/K, with R2 = 0.985. The 95 % confidence interval of predictions for glass in mass production largely depends on the glass composition of interest and the composition uncertainty. The model is valid for commercial silicate glasses containing Na2O