Notch and defect sensitivity under any kind of fatigue loading: an unifying approach

The present paper summarises on an attempt to link together two different engineering tools in order to propose an unifying approach suitable for predicting the material notch- as well as the material defect-sensitivity under multiaxial fatigue loading. The proposed approach takes as its starting point the assumption that the multiaxial fatigue limit of the parent material can initially be predicted by using the Modified Wöhler Curve Method recently proposed by Susmel and Lazzarin [1, 2]. This criterion postulates that the plane of maximum shear stress amplitude is coincident with the micro-crack initiation plane and its application requires the calculation of both the maximum shear stress amplitude and the maximum normal stress relative to the critical plane. According to the unifying diagram proposed by Atzori and Lazzarin [3, 4], the predicted multiaxial plain fatigue limit must then be corrected using both some LEFM concepts and the classical stress concentration factor, Ktg. The a...