The effect of compositional changes on the crystallization behaviour and mechanical properties of diopside–wollastonite glass-ceramics in the SiO2–CaO–MgO (Na2O) system

Abstract

The crystallization process of ternary system SiO2–CaO–MgO (Na2O) was investigated by DTA, XRD and SEM techniques and by strength measurements. The ability of Cr2O3+Fe2O3 as nucleating agents in inducing bulk nucleation via formation of a spinel phase was proved. Wollastonite and diopside are two major phases that were identified after two-stage heat treatment. The spherulitic growth morphology was observed by SEM. At high growth temperatures for long times the recrystallization process was observed too. The kinetic parameters, such as activation energy and Avrami exponent, were calculated by Kissinger equation.