KI of a circumferential crack emanating from an ellipsoidal cavity obtained by the crack tip stress method in FEM

In high hardness steel, fatigue crack appears from a microcavity in most cases. Therefore, it is important to know the stress intensity factor of a crack emanating from the cavity. Recently, a method for calculating the highly accurate values of two-dimensional stress intensity factors was proposed by Nisitani, based on the usefulness of the stress values at a crack tip calculated by FEM. This method is called the crack tip stress method. In this paper, the crack tip stress method is extended to the problems of an infinite solid having an ellipsoidal cavity with a circumferential crack emanating from the cavity subjected to tension.