BaO effect on the thermal properties of the phosphate glasses inside the Na2O –SrO–TiO2–B2O3–P2O5 system

• Glasses in the Na2O–SrO–BaO–TiO2–B2O3–P2O5 system were prepared by the conventional quenching method.
• Thermal and microhardness properties were carried out.
• Crystallization of the glasses by heat treatment at different temperatures is realized.
• Crystallization kinetic and the mechanism of the crystallization are discussed.

The glasses in the Na2O–SrO–BaO–TiO2–B2O3–P2O5 system were prepared by the conventional quenching route. In the present work, we studied the effect of BaSr substitution on some physical parameters such as density, molar volume, micro-hardness, glass transition temperature (Tg), and crystallization temperature (Tc) of series of glasses with the following composition 33.33Na2O–(10 − x)SrO − xBaO–10TiO2–30B2O3–16.67P2O5. The crystallization of the glasses by heat-treatments is performed and X-ray diffraction (XRD) showed the formation of a ferroelectric phase SrTiO3 and Na4Ba2(PO3)6 in their network. The kinetic of the crystallization is carried out by using DSC technique, and the activation energy and the Avrami parameter (n) are determined.