Effects of Al:Si and (Al + Na):Si ratios on the properties of the international simple glass, part I: Physical properties

Understanding composition-structure-property relationships of high-alumina nuclear waste glasses are important for vitrification of nuclear waste at the Hanford Site. Two series of glasses were designed, one with varying Al:Si ratios and the other with (Al + Na):Si ratios based on the international simple glass (ISG, a simplified nuclear waste model glass), with Al₂O₃ ranging from 0 to 23 mol% (0 to 32 wt%). The glasses were synthesized and characterized using electron probe microanalysis, X-ray photoelectron spectroscopy, small angle X-ray scattering, high-temperature oxide melt solution calorimetry, and infrared spectroscopy. Glasses were crystal free, and the lowest Na₂O and Al₂O₃ glass formed an immiscible glass phase. Evolution of various properties—glass-transition temperature, percentage of 4-coordinated B, enthalpy of glass formation—and infrared spectroscopy results indicate that structural effects differ based on the glass series.