Microstructural characterization and crystallization of (1-x)TeO2-xCdF2 (x=0.10, 0.15, 0.25 mol) glasses

The differential thermal analysis (DTA), X-ray diffractometer and scanning electron microscopy/energy dispersive spectrometer (SEM/EDS) techniques were used to investigate the microstructural characterization and the thermal behavior of the three (1 -x)TeO(2)-xCdF(2) (x=0.10, 0.15, 0.25 mol) glasses. The effect of the heating rate, annealing temperature and CdF(2) content on the thermal and the microstructural properties of TeO(2)-CdF(2) binary glasses were enquired. DTA analysis has shown that as the CdF(2) content in the glass composition increases, the value of the glass transition and the peak crystallization temperatures shift to higher values. SEM/EDS investigations have shown that the crystal formation of alpha-TeO(2), gamma-TeO(2) and CdTe(2)O(5) crystal phases were observed when the 0.90TeO(2)-0.10CdF(2) and the 0.85TeO(2)-0.15CdF(2) glass samples were annealed to temperatures above the crystallization temperatures. X-ray diffraction (XRD) results illustrated clearly the transformation of the metastable gamma-TeO(2) phase to stable alpha-TeO(2) crystalline phase as the annealing temperature was increased from 385 to 425 degrees C for the 0.75TeO(2)-0.25CdF(2) glass. (c) 2008 Elsevier Ltd. All rights reserved.