Results of phase transformations, enthalpy released and specific heat of Ge
22Se
78–xBi
x(
x=0, 4 and 8) chalcogenide glasses, using differential scanning calorimetry (DSC), under non-isothermal condition have been reported and discussed. The glass transition temperature,
T
g, is found to increase with an average coordination number and heating rates. Following Gibbs—Dimarzio equation, the calculated values of
T
g (i.e. 462.7, 469.7 and 484.4 K) and the experimental values (i.e. 463.1, 467.3 and 484.5 K) increase with Bi concentration. Both values of
T
g, at a heating rate of 5 K min
–1, are found to be in good agreement. The glass transition activation energy increases i.e. 102±2, 109±3 and 115±8 kJ mol
–1 with Bi concentration. The demand for thermal stability has been ensured through the temperature difference
T
c–
T
g and the enthalpy released during the crystallization process. Below
T
g, specific heat has been observed to be temperature independent but highly compositional dependent. The growth kinetic has been investigated using the Kissinger, Ozawa, Matusita and modified JMA equations. Results indicate that the crystallization ability is enhanced, the activation energy of crystallization increases with increasing the Bi content and the crystal growth of these glasses occur in 3 dimensions.This revised version was published online in November 2005 with corrections to the Cover Date.
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