Influence of modifiers on the thermal characteristic of glasses of the TeO2–P2O5–ZnO–PbF2 system

Abstract

A series of fluorotellurite glasses based on 70TeO2–5MxOy–10P2O5–10ZnO–5PbF2 in mol%, where MxOy = MgO, SrO, PbO, CdO, were prepared by the conventional melt-quenching method. The influence of modifiers on the thermal properties of glasses was analyzed. Thermal characteristics of glasses such as the transition temperature T g, the temperature for the crystallization onset T x, the maximum crystallization temperature T c, and the thermal stability parameter were determined by DSC method. Analysis of the local atomic interactions in the structure of glasses has been used to explain the course of the crystallization. The formation of crystalline phases was confirmed by X-ray diffraction analysis and SEM methods. Obtained results demonstrate that the new compositions lead to good thermal properties which make these glasses promising candidates for rare earth ions doping. Low value of the glass-forming tendency parameter K H indicates high tendency to devitrify. The kind of modifiers affects the crystallization process in fluorotellurite glasses.