Preparation of glass-ceramic in Li2O-Al2O3-GeO2-P2O5 system

Abstract

The results of preparation and structural characterization of glass-ceramics from the system Li2O-Al2O3-GeO2-P2O5 are shown in this paper. The crystallization behaviour of the selected glass was examined under non-isothermal and isothermal crystallization conditions. DTA, XRD and SEM methods were employed for analyses. It was confirmed that this glass crystallizes by the volume crystallization mechanism. The results also showed that the glass crystallize by primary crystallization. As a primary phase the LiGe2(PO4)3 is formed and the traces of GeO2 as a secondary one is present. The crystallization process occurred at a high homogeneous nucleation rate and the spherical morphology of crystal growth. By applying the Kissinger relation the activation energy of crystal growth Ea = 462 kJ/mol was determined.

Keywords

• germanium phosphate glass
• crystallization
• kinetics
• crystal growth