Glass-forming ability and thermal stability of Se100−x(Ge2Sb2Te5)x glassy alloys.

Glassy Se100−x(Ge2Sb2Te5)x (x = 5, 10, 15 and 20) bulk alloys were prepared by melt-quenched technique and studied by using differential scanning calorimetry at different heating rates under non-isothermal condition. The detailed thermal analysis shows that the glass transition temperature (Tg) depends on heating rates and x content. In particular, it is found that the glass-forming ability, thermal stability (Tc − Tg) and crystallization activation energy (Ec) increase with increased x content in amorphous Se, whereas glass transition activation energy (Eg) and fragility index (F) decrease with increased x contents. Variation in these parameters can be explained on the basis of network-forming ability of Se and bonding arrangement among the constituent atoms of alloys. [ABSTRACT FROM AUTHOR]