Crystallization and microstructure changes in fluorine-containing Li2O–Al2O3–SiO2 glasses

The nucleation and crystallization of Li2O–Al2O3–SiO2 glasses doped with 0, 0.4, 0.8 and 1.2 wt.% F− were investigated. With increasing fluoride content, the transformations from glass to β-quartz solid solution (β-quartz) and β-quartz to β-spodumene solid solution (β-spodumene) appeared at lower temperatures. The crystallization peak temperature (Tp) and activation energies (E) decreased, the Avrami exponent (n) and pre-exponential factor (ν) increased. The results suggest that fluoride promotes the initial crystallization and diffusion in the glass.