Compositional dependence of thermal stability, glass-forming ability and fragility index in some Se–Te–Sn glasses

摘要: Abstract Non-isothermal DSC thermograms were obtained for the ternary Se 90 Te 10− x Sn (  = 2, 4, 6 and 8) chalcogenide glasses in order to determine melting temperature T m , glass transition g onset c peak p temperatures of crystallization. These utilized investigate thermal stability through calculations difference  −  ), activation energy E t parameter S average value crystallization rate factor 〈 K 〉. In addition, forming ability was estimated by criteria reduced temperature, rg Hruby H R . The fragility index present determined see whether these materials are from strong or fragile glass-forming liquid. Results reveal that, both exhibit a maximum at  = 4 at.% Sn. Meanwhile, prepared liquid as evident calculations. compositional dependence above parameters discussed on basis Philips Thorpe topological model critical composition occurs an coordination number r 〉 = 2.16 but not 2.40. This is due formation iono-covallent bonds when doped with heavy elements like