Kinetic characterization of barium titanate-bismuth oxide-vanadium pentoxide glasses

The glasses with the composition (80 - x)V2O5 center dot 20Bi(2)O(3)center dot xBaTiO(3) with x = 2.5, 5, 7.5 and 10 mol % were prepared by a melting technique. The crystallization behavior and the microstructure of the glasses were investigated by using differential scanning calorimetry (DSC), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The mean value of the activation energy of structural relaxation (< E-g >) decreased from 395 +/- 3 to 369 +/- 1.83 kJ/mol when BaTiO3 increased from 2.5 to 10 mol %. The activation energies obtained by the methods Kissinger and Ozawa were in the range from 213 +/- 0.65 to 256 +/- 1.23 kJ/mol. Different analysis methods were used to estimate the Avrami exponents. Their values range from 4.26 +/- 0.6 to 2.62 +/- 0.11 for the exothermic peak of the prepared glasses. Moreover, synthesized glasses-ceramic containing BaTi4O9 and Ba3TiV4O15 were estimated by using XRD. (C) 2014 Elsevier Masson SAS. All rights reserved.