On effect of nonisothermal crystallization of BaO-Al O-SO Gel glass on its mechanicla properties

In this paper the research findings on how to improve mechanical properties of BAS glass-ceramic is presented. One very important part of the problem is the improvement of the crystallization rate. For both specimens, crystallization rate increase with increasing α, α being heating rate. Higher crystallization rate means finer grains and therefore higher mechanical properties. The kinetics of nonisothermal crystallization of specimens is studied and volume fraction of crystallization is calculated by a modified JMA equation. The crystallization process of gel glass is very fast due to the large interior surface area and nucleation density. When BaO is high and S₁O₂ is low, the activation energy of crystallization, E, and Avrami exponent, n, of the glass close to theoretical composition of barium feldspar are 522kJ/mol and 3.08 respectively. So the glass possesses the feature of bulk crystallization and its crystallization rate is higher than glass without such feature.