New oxyfluoroniobate glasses

Glasses based on niobium (V) oxyfluoride have been synthesized and characterized. Glass formation has been investigated in the NbO2F–BaF2 binary system and in ternary systems encompassing an alkali fluoride as the third component. Fast quenching is required to prevent melt crystallization, which results in thin samples. These glasses are stable at room atmosphere and in aqueous solutions. Density and characteristic temperatures have been measured for glasses with the general composition 40NbO2F–(60 − x)BaF2–xMF. Glass transition temperature Tg ranges between 300 and 400 °C while density decreases as alkali content increases. Chemical analysis of elements shows a good agreement between nominal and analyzed compositions.