Crystal growth kinetics of LiNbO3 crystals in Li2O–Nb2O5–SiO2–Al2O3 glass

Crystal growth kinetics of LiNbO3 in Li2O–Nb2O5–SiO2–Al2O3 glass has been investigated by the isothermal hold method. The crystallite size and the volume fraction crystallized were evaluated by X-ray diffraction analysis. Expressions were derived to allow calculation of crystal growth rate and nuclei density. The mechanism of crystal growth by nuclei coalescence in the clusters was verified by the decrease of the nuclei density of LiNbO3 in the glass during heat treatment. A simple diffusion-controlled model fitted the observed growth rate at the later stage of coarsening.