Abstract
The glass formation and devitrification of intermediate alloys in the Sb–Ge–Se system were studied by differential scanning calorimetry. A comparison of various simple quantitative methods to assess the level of stability of the glassy materials in the bove mentioned system is presented. All of these methods are based on characteristic temperatures, such as the glass transition temperature,
T
g
, the onset temperature of crystallization,
T
in
,
the temperature corresponding to the maximum crystallization rate,
T
p
, or the melting temperature,
T
m
.
In this case,
k
gl
may be more suitable for estimating the glass thermal stability in above composition range than Ω
T.
In this work the parameter
K
r
(
T)
is added to the stability criteria. The thermal stability of some ternary compounds of the Sb–Ge–Se type has been evaluated experimentally and correlated with the activation energies of crystallization by this kinetic criterion and compared with those evaluated by other criteria. All the results of criteria and kinetic parameter
K
r
(
T)
confirm that the thermal stability decrease with increasing Sb content in the glassy system. The crystallization results are analyzed and both the activation energy of crystallization process and the crystallization mechanism are characterized. Finally, identification of the crystalline phases was made by recording the X-ray diffraction pattern of the transformed material. This pattern shows the existence of microcrystallites of two phases, the first is germanium Selenide GeSe
2
and the second is Sb
2
Se
3
in amorphous matrix for annealed of Sb
2.5
Ge
22.5
Se
75
and Sb
10
Ge
15
Se
75
glass.