TEMPERATURE-DEPENDENCE OF THE HIGH-FREQUENCY VISCOELASTIC BEHAVIOR OFA SODA-LIME-SILICA GLASS

The high-frequency viscoelastic behavior of a soda-lime-silica glass h as been investigated using the Brillouin scattering technique. The tem perature dependence of instantaneous elastic constants and very short- time relaxation mechanisms have been measured in a temperature range b etween 100 degrees and 1000 degrees C. Variations in the elastic const ants in the transition region are significant, and have to be taken in to account for numerical computations of tempering and annealing of gl asses. A complex thermorheological behavior is observed for very fast relaxation mechanisms in the transition range, whereas intermediate an d slow relaxation mechanisms exhibit a simple thermorheological behavi or. The viscoelastic behavior of this glass can be adequately represen ted by assuming a different thermorheological behavior in the alpha- a nd beta-relaxation regimes.