Localized versus diffuse damage in amorphous materials.

Based on a Griffith approach, we study the behavior of disordered media constituted at the microscale by distributions of elastic and breakable links with variable activation and fracture thresholds. Depending on the microscopic distribution properties, the material may be characterized by an unstable strain domain, which gives the possibilities of having homogeneous or localized damage. Our simple model delivers a theoretical scheme to describe main experimental effects observed at the microstructure and macroscopic scale in disordered materials undergoing damage and relates them to the inhomogeneity properties of the material.