Structure and thermo-mechanical response of Na2O-TiO2-SiO2 glasses to temperature

In-situ high temperature Raman spectroscopy, Brillouin light scattering (BLS), and dilatometry have been used to study the structure and properties of xNa2O-yTiO2-(1-x-y)SiO2 glasses. Glasses with compositions x = 10, 15, 20, and 25, and y = 4, 7, and 10 were prepared through a traditional melt-quench method. Addition of Na2O decreases the temperature response of elastic moduli and increases the temperature response of the Poisson's ratio and the coefficient of thermal expansion (CTE). TiO2 increases the magnitude of elastic moduli, but does not change their responses to temperature appreciably. TiO2 has a much smaller effect in changing the CTE and the Poisson's ratio than Na2O. Changes in the position and intensity of Raman peaks with temperature have been discussed. Changes in the temperature responses of mechanical and material properties have been correlated to the underlying structural changes reflected in the temperature responses of Raman peak positions and intensities.