A damage mechanics-based fatigue life prediction approach for 30crmnsia alloy steel with impact defect

Based on the continuum damage mechanics theory, the fatigue life prediction for 30CrMnSiA alloy steel with impact defect is conducted. At first, the damage evolution equations to calculate the initial plastic damage and multiaxial fatigue damage are derived. Then the method to calibrate three kinds of material parameters for 30CrMnSiA alloy steel is proposed and all the material parameters are obtained. The damage mechanics-finite element method to predict the fatigue life is used, in which the coupling relation between damage field and stress field is taken into account. At last, the fatigue life of 30CrMnSiA alloy steel with impact defect is predicted and the fatigue test is conducted to validate the aforementioned approach.