SrO effect on the structure, phase separation and crystallization kinetics of [formula omitted] glasses

Abstract

29SiO2−20B2O3−24.5Na2O−2ZrO2−(24.5−x)CaO−xSrO (x = 0, 5, 10, 15 (wt%)) glasses are studied for their non-isothermal crystallization kinetics, thermal, structural, and phase separation characteristics. The glass transition, crystallization, and peak crystallization temperature are obtained from the differential thermal analysis (DTA) curves. The characteristic temperatures shift to higher temperature with the increasing heating rate. Increase in the SrO concentration results in a decrease in Tg.The values of activation energy of glass transition and crystallization calculated using Kissinger and Augis-Benett models lie in the range 256–397 kJ/mol and 174–350 kJ/mol, respectively. Structural properties are analyzed using Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy. Introduction of SrO results in variation in the BO4,BO3,andQn units in the borosilciate network. This can be used to obtain information about the structure-composition relation in the synthesized glasses. As the SrO concentration increases, the variation in the fraction of BO4 and Q2 structural units follow an opposite trend.