Dynamic effect in the fatigue fracture of viscoelastic solids

Crack growth in viscoelastic solids under cyclic loading tends to be faster than that under static loading with the same amplitude. This phenomenon, known as dynamic effect , is a key mechanism underlying the fatigue fracture of soft viscoelastic polymers, but its physical nature remains a mystery. We develop a scaling theory to delineate how viscoelastic dissipation associated with crack growth is governed by the coupling between three time-dependent processes: cyclic loading, crack growth and viscoelastic creep. In the limit of slow crack growth and slow cyclic loading, a simple integral equation is derived to predict the crack growth velocity under different cyclic loading frequencies. (C) 2022 Elsevier Ltd. All rights reserved.

Automated summary

In this study, a scaling theory is developed to understand the dynamic effect of crack growth in viscoelastic solids under cyclic loading. The coupling between cyclic loading, crack growth, and viscoelastic creep is found to govern the viscoelastic dissipation. A simple integral equation is derived to predict the crack growth velocity under different cyclic loading frequencies.