A critical plane-based criterion for high-cycle multiaxial fatigue using averaged principal stress directions

A high-cycle multiaxial fatigue criterion based on the so-called critical plane approach has recently been proposed by the present authors. Accordingly, the critical plane orientation is correlated to some averaged directions of the principal stresses, whereas other criteria available in the literature determine this orientation by maximizing the amplitude and/or the maximum value of some stress components. Then, fatigue strength estimation is performed by considering a quadratic combinations of the shear stress amplitude and the maximum value of the normal stress acting on the critical plane. The application of the proposed criterion for evaluating the endurance limit requires the knowledge of three material parameters: the fatigue limit under fully reversed normal stress, the fatigue limit under fully reversed shear stress, the slope of the S-N curve in the high-cycle regime for fully reversed normal stress. The purpose of the present paper is to critically highlight the main characteristics of the criterion.