Thermal Stresses, Relaxation, and Hysteresis in Glass

Abstract

The theory of A. R. Cooper, Jr., and other viscoelastic theories of thermal stresses in glass are reviewed. The role of structural relaxation in the evolution of the free strain and stress relaxation times is examined. An explanation of the hysteresis loop observed on thermal contraction/expansion curves in the glass transition region is offered. Single‐exponential models are reviewed on the merit of the insight they provide into the physics of stress development. Their numerical performance is compared with that of the more comprehensive theories.