Accurate measurements of the apparent specific heat below and through the glass transition in slowly cooled Gex(Se85Te15)100-x glasses (x = 0, 2 and 10) were performed using differential scanning calorimeter. The enthalpy released by the glasses when annealed near the glass transition was deduced. The kinetics of coordination short range ordering (CSRO), structural relaxation and the glass transition were studied by continual heating as well as by isothermal methods of thermal analysis. The activation energies of structural relaxation ΔE* were observed to be similar for all samples, as was the qualitative correlation of their absolute values which ranged from 120-143 kJ (g atom)-1 for CSRO processes at Ta = Tg - 60 K, to 217 kJ (g atom)-1 for glass transformation processes in glass having x = 10, as determined by various methods of kinetic analysis (Kissinger, Moynihan, activation energy spectrum and distribution of non-linear relaxation models). This may be explained by assuming first-order kinetics and a wide spectrum of relaxation times. © 1994.
|Journal||Materials Science and Engineering B|
|Publication status||Published - 1 Jan 1994|