Fatigue life and defect tolerance calculation for specimens with foreign object impact and scratch damage

In this paper, a new method is proposed to calculate the fatigue life and defect tolerance for a 30CrMnSiA steel specimen with foreign object impact damage and scratch damage. First, the processes of foreign object impact and scratch are simulated. Then, the Lemaitre’s plasticity damage model is adopted to calculate the initial damage field arising from the impact process and scratch process. Second, the Chaudonneret’s damage model is applied to calculate the fatigue damage for the specimen with a defect under multiaxial fatigue loading. Then, the FE implementation of the damage mechanics model is presented in the platform of ANSYS, in which the coupling effect between the stress and damage fields is considered. Finally, this proposed method is applied to fatigue life and defect tolerance calculation for the 30CrMnSiA steel specimen with an impact defect and a scratch defect. The experiments were conducted to evaluate the approach mentioned above.