On the effect of stress on the nonequilibrium viscosity of glasses

Two processes related to the relaxation of a glassy material’s structure were discussed. One entails stress relaxation, while the other involves the relaxation of the structure to its equilibrium state following the stress relief and is described by the change of fictive temperature. Both processes affect the viscosity coefficient. The nonequilibrium viscosity model was analyzed with account of these relaxation processes. The importance of considering stresses when modeling the viscoelastic behavior of glassy materials was showcased by solving the problem of stress relaxation in a plate under thermal stresses.