Fatigue Life Prediction Under Multiaxial Variable Amplitude Loading Using A Stress-Based Criterion

This article presents fatigue life calculations for metals under different multiaxial variable amplitude loading patterns. Developed from a stress-based multiaxial fatigue criterion, a damage parameter used in the fatigue life prediction method can capture correctly different damage mechanisms (proportional and non-proportional multiaxiality, mean stress, asynchronous and variable amplitude) of fatigue loading in the high cycle fatigue domain. The method is based on a reference S-N curve and a cumulative damage law. Assessment of the accuracy of the proposed method is carried out with three different materials from literature (EN-GS800-2 cast iron, 39NiCrMo3 steel and SAE 1045 steel) subjected to different patterns of variable amplitude loading (blocks, non-proportional asynchronous and proportional random loading). Results reveal that the prediction method is in good accordance with the experimental data.