Critical Plane Fatigue Analysis of Various Constant Amplitude Tests for SAE1045 Steels

A large number of published constant amplitude test results, in-phase as well as out-of-phase, on SAE 1045 steels are analysed here in an attempt to evaluate the general applicability of several damage parameters to complex multiaxial cyclic loadings. The critical plane approach is adopted and the calculated results from various constant amplitude tests are directly compared on a damage parameter versus fatigue life plot. It is found that while many damage parameters can predict fatigue life for in-phase constant amplitude loadings within a factor of two of the observed life, only two biaxial type of parameters evaluated here can consistently produce acceptable fatigue life prediction for out-of-phase constant amplitude loadings.