Crystallization Kinetics and Phase Transformation of Li₂O–Fe₂O₃–MnO₂–CaO–P₂O₅–SiO₂ Glass

The crystallization kinetics and phase transformation of 10Li₂O–14Fe₂O₃–11MnO₂–25CaO–5P₂O₅–35SiO₂ (LFMCPS) glass have been investigated using differential thermal analysis (DTA), Χ-ray diffraction (XRD), and scanning electron microscopy (SEM). The major crystalline phase determined by XRD analysis was triphylite [Li(Fe_0.5Mn_0.5)PO₄], β–wollastonite (β CaO SiO₂) and magnetite (Fe₃O₄) as the minor phases. The nonisothermal kinetics of crystallization of the LMFCPS glass was investigated using DTA analysis. The activation energy of crystallization for LFMCPS glass was 74.6 kcalymol. The growth morphology parameter n was 0.98 at a heating rate of 5 °C/min and decreased to 0.74 as the heating rate increased to 20 °C/min. The numerical factor of crystallization mechanism m was 0.57 at low crystallization temperature and gradually decreased as the temperature increased. For the experiment, the parameters n and m were approximately one. These results indicated that the surface nucleation was dominant in LFMCPS glass crystallization.