Abstract:
This paper presents a new model to estimate multiaxial high cycle fatigue life of steel joints, when it is subjected to variable amplitude proportional loadings. The considered failure mechanism of proposed model is in mesoscopic scale (grain scale). The model mainly consists of a new damage indicator, which gives a better prediction to fatigue life than existing fatigue models. The verification of the proposed fatigue model is performed by comparing the experimental fatigue lives with theoretical predictions. It is shown that the proposed multiaxial fatigue model gives much more realistic fatigue life than previous models in both variable amplitude and random loading conditions. Finally, proposed model is applied to estimate fatigue life of a steel joint and associated procedure is clearly indicated.