FATIGUE UNDER OUT‐OF‐PHASE BENDING AND TORSION

Abstract

Abstract Test data on fatigue under out‐of‐phase bending and torsion has been reanalysed. For the materials tested failure has been found to be consistent with the plane of maximum range of maximum range of maximum principal stress, as for the in‐phase case. The critical shear planes are assumed to be those associated with this principal stress plane. A multiaxial fatigue damage parameter based on the maximum range of shear stress on the critical shear plane allowing for the effect of the range of normal stress occurring on this plane has been used to develop a proposed set of design curves for in‐phase bending and torsion which are conservative for the long life out‐of‐phase case.