Glass transition and crystallization kinetics of a barium borosilicate glass by a non-isothermal method

• DOI: 10.1063/1.4863334
• Publication Date: 2014-01-29T01:30:32Z
• Authors: Andreia A. S. Lopes; Roque S. Soares; Maria M. A. Lima; Regina C. C. Mont...
• Keywords: Exothermic reaction; Barium; Barium borate; Endothermic process; Isothermal process

The glass transition and crystallization kinetics of a with molar composition 60BaO-30B2O3-10SiO2 were investigated by differential scanning calorimetry (DSC) under non-isothermal conditions. DSC curves exhibited an endothermic peak associated the two partially overlapped exothermic peaks glass. dependence temperature (Tg) maximum (Tp) on heating rate was used to determine activation energy (Eg), for (Ec), Avrami exponent (n). X-ray diffraction (XRD) revealed that barium borate (β-BaB2O4) first crystalline phase be formed followed formation silicate (Ba5Si8O21). variations fraction (χ) also examined. When increased from 0.1 0.9, value local (Ec(χ)) decreased 554 458 kJ/mol 1104 831 second peak. determined near 2 indicating similar one-dimensional mechanism both phases. This confirmed morphological studies performed electron microscopy (SEM) samples heat-treated at temperatures.