Structural Relaxation of Enthalpy and Heat Capacity of As2Se3 Glass.
CATHOLIC UNIV OF AMERICA WASHINGTON D C VITREOUS STATE LAB
Pagination or Media Count:
Differential scanning calorimetry measurements of the enthalpy of As2Se3 glass during structural relaxation in the glass transition region have been carried out for two time-temperature programs rate heating at 10Kmin following a cool at a constant rate and isothermal annealing following a temperature step from an equilibrium state. The kinetic parameters for the structural relaxation assessed from the rate heating data gave an accurate prediction of the evolution of the enthalpy during isothermal annealing. The heat capacities of As2Se3 glasses cooled through the transition at rates ranging from -20 to 0.31 Kmin were independent of cooling rate within experimental precision 0.2. In this respect As2Se3 is unlike previously studied glasses, whose heat capacities show a more sizeable dependence on thermal history.
- Ceramics, Refractories and Glass
- Atomic and Molecular Physics and Spectroscopy