Critical Plane Approach-Based Fatigue Life Prediction for Multiaxial Loading: A New Model and its Verification

The results of a comparative analysis of five models of multiaxial fatigue based on the concept of the critical plane are presented. The Fatemi–Socie, Wang–Brown, Wu–Hu–Song, and augmented generalized strain energy models were studied. The durability calculated by these models was compared with experimental data obtained for 10 metal alloys and six multi-axis loading paths. The data analysis showed that the prediction of durability under multiaxial loading can be improved by using a fatigue damage parameter that includes the maximum shear strain and the square of the linear strain at the maximum shear site. The proposed model can be considered a new variant of the Brown-Miller model, where for the first time the fatigue damage parameter was presented as the sum of the maximum shear strain and the linear strain at the maximum shear site. It is shown that this model correlates well with the experimental data for both proportional and non-proportional loading.