تعيين انرژي فعالسازي بلورينگي و پايداري گرمايي شيشه هاي TeO2 - V2O5 - Sb2O3

Determination of the crystallization activation energy and thermal stability of TeO2- V2O5- Sb2O3 glasses

In this work, the bulk samples of 40TeO2-(60-x)V2O5-xSb2O3 amorphous composition with different molar percentage0≤x≤10 were prepared by rapid melt-quenching method. Differential scanning calorimetry (DSC) at different heating rates (φ) was used to thermal analyze and to gain more insight in to the thermal stability, glass forming tendency and so calorimetriccharacteristics of the present glasses. The glass transition temperature (Tg) ,the temperature corresponding to the onset of crystallization (Tx) and also the crystallization temperature (TCr) were obtained at different heating rates, to estimate the key kinetic parameter of activation energy of crystallization(ΔE) by using ozawa and kissinger methods. Generally, results of this work show that the glass with x=10 has the highest thermal stability and glass forming tendency and so has very good resistance against thermal attacks; the sample whit x=5 shows a sharp decrease in the crystallization activation energy, which can be resulted by increasing of non-bridging oxygenʹs.