Enthalpy relaxation in GexSe1-x chalcogenide glasses

Enthalpy relaxation in selenium samples and GexSe1-x alloys with x=0.08 and 0.12 has been investigated by differential scanning calorimetry. All the samples have been submitted to comparable aging temperatures 10 degrees C below the glass transition temperature for a period from 0.5 to 800 h. The apparent activation energy and the Narayanaswamy parameter, X, were calculated and the non-exponentiality parameter, beta, was estimated for the samples. The introduction of the germanium atoms in the selenium chain changes the distribution of relaxation times, increases the relaxation rate per decade and decreases the apparent activation energy. No differences were observed in the GexSe1-x alloys in the evaluation of these parameters. (C) 1998 Published by Elsevier Science B.V. All rights reserved.