Fatigue Life Prediction of Notched Specimens Using a new model in the framework of Entropy Generation Theory

In this paper, a new entropy based criterion is proposed, and applied to fatigue life prediction of the notched specimens subjected to remote constant amplitude displacement. The hypothesis of proposed approach is, the accumulation of generated entropy up to the final failure might be constant, independent of load, geometry and frequency. The plastic energy measured from hysteresis loops of fatigue loading considered as the only driver of entropy generation. In order to extract hysteresis loop of fatigue cycles, an elasto-plastic constitutive model is employed considering the non-linear kinematic hardening of Chaboche in the ABAQUS software capabilities. The results of proposed approach are evaluated by fatigue test results of the Al-7075-T6 and Al-2024-T42 specimens subjected to tension-tension loading. Finally, by comparing the results of the proposed method with the obtained results of wellknown strain based criteria, it is shown that the proposed method has a more accurate prediction lives than other methods.