Investigation of the mixed-mode fatigue crack growth of a hot-rolled steel plate with a circular microdefect

The interaction between cracks and microdefects under mixed-mode loading conditions is important for precisely estimating the fatigue lifetime of a structure. In this study, the fatigue crack growth behavior of a crack with a circular microdefect is investigated under mixed-mode loading conditions experimentally using modified compact tension shear (CTS) specimens for various loading angles with/without a circular microdefect. The fatigue crack growth behavior observed through experiments is analyzed by linear elastic finite element (FE) analyses and the simulated crack path using the maximum tangential stress (MTS) criterion is compared and discussed with the crack path observed through experiments.