Crystallization Kinetics and Characterization of Nanostructure Mica Glass-Ceramics with Optical Transparency

Transparent glasses in a system of Li2O-MgO-SiO2-Al2O3-Fchemical constituents were prepared by melt quenching method. In the fabrication of nanocrystal glass-ceramics, controlled nucleation and subsequent crystal growth were necessary to avoid loss of transparency. It was therefore important to understand thermal properties and crystallization kinetics of the glass ceramics. The crystallization behavior of the prepared glass was investigated by DTA, XRD and SEM. By crystallization heat-treatment, various crystalline phases, microstructure and transmittance were obtained. The sellaite was first precipitated as the nuclei before the crystallization of mica and then mica nanocrystals were precipitated with average size of <40 nm. In this respect, the nucleation process was optimized in order to achieve a fine mica microstructure.