Viscous effects in brittle fracture

Abstract

We use lattice simulations to study the dynamics of cracks under applied strains in brittle materials in the presence of substantial viscous dissipation. This is probably a physically relevant limit in real brittle materials. In large samples, cracks accelerate in the absence of viscous effects and become unstable against branching. With viscosity, cracks have a limiting velocity and long straight cracks can be stable.