Structural Dependence of Physical Properties in Sodium Boroaluminosilicate Glasses

Boroaluminosilicate glasses have found applications in many fields. The extent and nature of the mixing of network formers like SiO2, B2O3, and Al2O3 play an important role in controlling the macroscopic properties. To understand the structure-property correlations in these glasses, we study a series of sodium boroaluminosilicate glasses with various [Al2O3]/[SiO2] ratios to access different regimes of sodium behavior. We determine dynamic properties, elastic moduli, and hardness of these glasses. The results reveal an existence of local minimum for density, fragility index, Young’s and shear moduli, and hardness around [Al2O3]-[Na2O]=0. Moreover, there exist three compositional response regions for elastic moduli and hardness. These results are explained in terms of topological constraint theory.