Local approach and micromechanical modelling of fracture

After an introduction into the phenomenae of brittle and ductile fracture of steels the lecture will present various micromechanical models covering different aspects of the failure process. Emphasis will be laid on the applicatin of those models covering in particular the Weibull cleavage stress, the Rice and Tracey void growth model, and the Gurson model as modified by Needleman and Tvergard. Whenever possible, the comparison of experimental and numerical results will be stressed. In conclusion, the future potential of micromechanical models will be sketched, e.g., application to other materials like composites or towards optimization of existing and design of new materials. (orig.)