Structural Integrity Assessment by Models of Ductile Crack Extension in Sheet Metal

Methods for analytical and numerical simulation of ductile crack extension are used for the prediction of tolerable loads and residual strength of a structure. They cover a wide range from relatively modest phenomenological approaches which allow quick and inexpensive analyses to elaborate micromechanical models, in particular an analytical flaw assessment model, a finite element model which uses the crack tip opening angle as controlling parameter, a cohesive zone model and a ductile damage model. The various phenomenological and micro‐mechanical models constitute elements of an overall concept of damage analysis designated as Structural Integrity Assessment Method (SIAM). The contribution gives an overview over the respective concepts and equations and explains the application of these models by examples of numerical simulations of crack extension in metal sheets. The models are compared with respect to their capabilities, advantages, limitations and drawbacks.