MODELLING OF CRACK PROPAGATION IN POLYCRYSTALLINE MEDIA

摘要

A model of crack propagation in a polycrystalline material is presented. It uses local, microstructural considerations to evaluate macroscopic behaviour. The effects of morphological texture (grain size and shape) and mechanical loading mode have been considered in both cleavage and intergranular propagation modes. Results reproduced experimental tendencies: a reduction of the grain size increases the toughness and favours cleavage fracture, changes in the shape factor of the grains can increase or decrease the toughness, depending upon the loading mode.