Stress Intensity Factors of Semi-elliptical Surface Cracks in Bending

Abstract

The stress intensity factors of semi-elliptical surface cracks in a finite thickness plate subjected to bending were estimated by taking account of the front free surface magnification factor for stress intensity component due to linearly varying pressure, which was neglected in the well-known calculation by Shah and Kobayashi. The stress intensity factors obtained were somewhat smaller than those given by Shah and Kobayashi, and gave a reasonable estimate of the propagation rate of part-through cracks by fatigue, in the case where the crack length in the depth direction was less than a half of the plate thickness.