Crystallization study of Sn additive Se–Te chalcogenide alloys

Results of differential thermal analysis (DTA) under non-isothermal conditions of glasses Se90 − xTe10Snx (x = 0, 2.5, 5 and 7 at.%) are reported and discussed. The glass transition temperature (Tg), the onset crystallization temperature (Tc) and the peak temperature of crystallization (Tp) were found to be dependent on the compositions and the heating rate. Values of various kinetic parameters such as activation energy of glass transition (Eg), activation energy of crystallization (Ec), rate constant (Kp), Hurby number (Hr) and the order parameter (n) were determined. For the present systems, the results indicate that the rate of crystallization is related to thermal stability and glass forming ability (GFA). According to the Avrami exponent (n), the results show a one dimensional growth for the composition Se90Te10 and a three dimensional growth for the three other compositions. The crystalline phases resulting from DTA and (SEM) have been identified using X-ray diffraction.