An extensive study on the prediction of elastic properties in oxyfluoride tellurite AlF3-ZnO-TeO2 glasses under the substitution of TeO2 by AlF3

摘要

In this article, we have presented an extensive study on the prediction of elastic properties in five series of oxyfluoride tellurite glasses with molar compositions xAIF(3)-1ZnO-(99-x)TeO2, xAlF(3)-3ZnO-(97-x)TeO2, xAlF(3)-5ZnO-(95-x)TeO2, xAlF(3)-7ZnO-(93-x)TeO2 and xAlF(3)-10ZnO-(90-x)TeO2. Structural changes due to the substitution of TeO2 by AlF3 have been explored by interpreting the compositional dependence of elastic moduli and Poisson's ratio in terms of fractal bond connectivity, field strength of the interstitial cations, molar volume and dissociation energy per unit volume of the glass. The correlation between bulk modulus and the ratio between packing density and mean atomic volume has been carried out according to the recently presented Abd El-Moneim & Alfifi's semi-empirical formula. In addition to this, the theoretical values of elastic moduli and Poisson's ratio were calculated on the basis of Makishima Mackenzie's theory as well as the Rocherulle et al model and compared with the experimental values. It has been found that the ratio between packing density and mean atomic volume can be considered as a good factor for predicting changes in the elastic moduli of the investigated oxyfluoride tellurite glasses. The agreement between theoretical and experimental elastic moduli and Poisson's ratio is excellent for majority of the samples. The slight discrepancy between some of the experimental and theoretical values was discussed in terms of the basic structural units constituting the glass network.