Effect of Fe2O3 on non-isothermal crystallization of CaO-MgO-Al2O3-SiO2 glass

The crystallization behavior and kinetics of CaO-MgO-Al2O3-SiO2 (CMAS) glass with the Fe2O3 content ranging from zero to 5% were investigated by differential scanning calorimetry (DSC). The structure and phase analyses were made by Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD). The experiment results show that the endothermic peak temperature about 760 degrees C is associated with transition and the exothermic peak temperature about 1000 degrees C is associated with crystallization. The crystallization peak temperature decreases with increasing the Fe2O3 content. The crystallization mechanism is changed from two-dimensional crystallization to one-dimensional growth, and the intensity of diopside peaks becomes stronger gradually. There is a saltation for the crystallization temperature with the addition of 0.5% Fe2O3 due to the decomposition of Fe2O3. Si-O-Si, O-Si-O and T-O-T (T=Si, Fe, Al) linkages are observed in Fe2O3-CaO-MgO-Al2O3-SiO2 glass.