Article

Thermal properties of multicomponent tellurite glass

Journal of Materials Science (Impact Factor: 2.31). 04/2008; 43(15):5131-5138. DOI: 10.1007/s10853-008-2737-4

ABSTRACT Quaternary tellurite glass systems of the form 80TeO2–5TiO2–(15−x)WO3−xAnOm where AnOm is Nb2O5, Nd2O3, and Er2O3, x=0.01, 1, 3, and 5mol% for Nb2O5 and x=0.01, 0.1, 1, 3, 5, and 7mol% for Nd2O3 and Er2O3, have been prepared by the melt quenching. Density and molar volumes have been measured and calculated for every glass system.
The thermal behavior of the glass series was studied by using the differential thermal analysis DSC. Glass transition temperature
T
g, crystallization temperature T
c, and the onset of crystallization temperature T

x
were determined. The glass stability against crystallization S (≈100°C) and glass-forming tendency K
g (≈0.3) have been calculated. Specific heat capacity C
p (≥1.4J/g°C) was measured from room temperature and above the T
g for every composition in each glass series. Quantitative analysis of the above thermal properties of these new tellurite
glass with the structure parameters like average cross-link density
$ \ifmmode\expandafter\bar\else\expandafter\=\fi{n}_{{\text{c}}} $ \ifmmode\expandafter\bar\else\expandafter\=\fi{n}_{{\text{c}}} (≥2.4), number of bonds per unit volume n
b (≥8×1028cm−3), and the average stretching force constant (F) have been studied for every glass composition.

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