DAMAGE SIMULATION IN HETEROGENEOUS MATERIALS FROM GEODESIC PROPAGATIONS

Abstract

We propose a simplified method to simulate damage evolution in heterogeneous media from geodesic propagation calculations. The method introduced for the case of porous media (polycrystalline graphite), was generalized to multiphase media, and then to a continuous variation of local fracture energy. It is based on a minimization of the fracture energy criterion, ignoring the local variations of the stored strain energy. With this simplification, the microcracking process is simulated by very efficient algorithms, involving a low calculation cost, to extract minimal paths on graphs with edges valued according to the local fracture energy. From the simulations, made on micrographs in materials or on random microstructure simulations, we get images of the possible microcracks paths, to be compared with real cracking of materials, and an estimation of the effective toughness of heterogeneous materials. Our approach is illustrated from two‐dimensional simulations corresponding to various types of microstructure involving the following micro‐geometrical distributions of the local fracture energy: isotropic and anisotropic two‐phase media, polycrystal with cleavage and intergranular fracture, material with a continuous distribution of surface energy.