Enthalpy relaxation of hyperquenched glasses and its possible link to α- and β-relaxations

The enthalpy relaxation of glass fibers of different chemical compositions and thereby of different fragility steepness indices is investigated by means of the hyperquenching–annealing–DSC scanning method. Results show that the pattern of the enthalpy relaxation spectra of the glass depends on its composition, and, hence, on its fragility steepness index. The present paper suggests that the enthalpy relaxation pattern could be linked to the α- and β-relaxations that are normally used to describe relaxation spectra of supercooled liquids near the glass transition. Three observations are shown to support the suggestion.