Crystallization kinetics of Pb12Ge12Se76 chalcogenide glass

The differential thermal analysis technique is used in testing the crystallization kinetics of Pb12Ge12Se76 glass at different heating rates (2.5, 5, 10, 15, and 20 K/min). The glass is thermally stable. The activation energy for glass transitions E-g using the Kissinger, Augis-Bennett, and Moynihan models is 89.4, 92.1, and 94.7 kJ/mol, respectively. The activation energy of crystallization E-c using the models, Kissinger, Augis-Bennett, Moynihan, Gao et al., Matusita, Friedmann, Flynn-Wall-Ozawa, and Kissinger-Akahira-Sunose is 266.7, 271.4, 276.1, 257.4, 270.9, 306.8, 288.7, and 279.3 kJ/mol, respectively. In studying normalized z(alpha) and y(alpha) as functions of conversion for processes of the crystallization peak at different heating rates, the values of alpha(max,z) are 0.657, 0.634, 0.617, 0.612, and 0.639 for rates (2.5-20 K/min) of the average value 0.632, so the JMA model was applied. Also, the values of alpha(max,y) found to be smaller than those of alpha(max,z).