화학공학소재연구정보센터
Thermochimica Acta, Vol.345, No.1, 13-17, 2000
Studies on GexSb40-xSe60 glasses by differential scanning calorimetry and thermomechanical analysis
Calorimetric and dilatometric thermal properties of bulk GexSb40-xSe60 glasses (x = 15, 20, 25, 27, 32, 35) have been investigated by differential scanning calorimetry (DSC) and thermomechanical analysis (TMA). The variations of the difference in specific heat capacity between glass and undercooled liquid... Cp and of the glass-transition temperature Tg on the average coordination number Z have been specified. It has been found from the dependence of T-g on the heating rate that the parameter B, related to configurational changes in the structure, reaches a maximum at Z = 2.67 (i.e. for Ge-27 Sb-13 Se-60), while Delta C-p values remain almost constant at Z 12.67. The apparent activation energy of glass transition E-t for both the methods has been compared. Threshold-like behaviour at Z = 2.67 of the change in the fragility in has also been observed for both the methods. The softening temperature T-s and the coefficient of thermal expansion in glass alpha(g) determined by TMA have exhibited a feature at Z = 2.67 as well.