Influence of NiO on the crystallization kinetics of near stoichiometric cordierite glasses nucleated withTiO2

Abstract

This work presents the effect of NiO on the thermal behavior and the crystallizationkinetics of glasses lying near the stoichiometric cordierite composition nucleated withTiO2. Three glasses with NiO content varying between 1 and 5 mol% have been synthesized inPt crucibles. Activation energies for structural relaxation and viscous flow have been calculatedusing the data obtained from differential thermal analysis (DTA). Kinetic fragility of theglasses along with other thermal parameters has been calculated. Non-isothermalcrystallization kinetic studies have been employed to study the mechanism of crystallization inall three glasses. The crystallization sequence in the glasses has been followed by x-raydiffraction analysis of the heat treated glass samples in the temperature range of800–1200 °C. μ-cordierite has been observed to be the first crystalline phase in all the glass samples after heat treatmentat 850 °C, while NiO plays an important role in determining the crystallizationsequence at higher temperatures, leading to the formation ofα-cordierite.