A study on the thermal stability of some alloys in the Cu-Ge-Te glassy system by differential scanning calorimetry

The glass formation and devitrification of alloys in the Cu-Ge-Te system we re studied by differential scanning calorimetry. A comparison of various si mple quantitative methods to assess the level of stability of the glassy ma terials in the abovementioned system is presented. All of these methods are based on characteristic temperatures such as the glass transition temperat ure, T-g, the onset temperature of crystallization, T-in, the temperature c orresponding to the maximum crystallization rate, T-p or the melting temper ature, T-m. In this work, the parameter K-r(T) is added to the stability cr iteria. The thermal stability of some ternary compounds of the CuxGe0.2-yTe 0.80-x+y type has been evaluated experimentally and correlated with the act ivation energies of crystallization by this kinetic criterion and compared with those evaluated by other criteria. (C) 1999 Elsevier Science B.V. All rights reserved.