A new high-cycle fatigue criterion applied to out-of-phase biaxial stress state

A new multiaxial high-cycle fatigue criterion based on the so-called critic al plane approach is presented. According to such a criterion, the critical plane orientation is proposed to be correlated with the averaged principal stress directions deduced through the weight function method. Then the fat igue failure assessment is performed by considering a nonlinear combination of the maximum normal stress and the shear stress amplitude acting on the critical plane. The proposed criterion is applied to a general sinusoidal b iaxial stress state, for which analytical formulae can be derived. The theo retical results calculated according to the present criterion, together wit h those of other common critical plane criteria, are compared with experime ntal data related to different brittle (hard) metals under in-phase or out- of-phase sinusoidal biaxial normal and shear stress states. (C) 2001 Elsevi er Science Ltd. All rights reserved.