2D-and 3D-mixed mode fracture criteria

Mixed-Mode loading of cracks occurs if due to the loading of the component or the OF orientation of the crack the fundamental modes of crack loading (Mode I, Mode II Mode III) occasionally or permanently appear in combination, i.e. the loading of the component causes a nonsymmetric singular stress field. The stress field in the vicinity of the crack tip is therefore not only defined by the stress intensity factors K-II and/or K-III. In course of this paper 2D- and 3D-Mixed Mode fracture criteria to determine the situation of unstable crack growth will be presented and compared with each other. Besides these fracture criteria new fatigue crack growth criteria for multiaxial loading will be presented.