A New Method of Fatigue Life Prediction for Notched Specimen

The simulations of the notched specimens under multiaxial loading were conducted by finite element method. The simulation results show that the stress gradient increases with the decrease in notch radius for the same strain path. The equivalent strain method is used to predict the fatigue life based on the strain at the notched root. The prediction results are more conservative with the decrease in notch radius. The effective distance is determinated by the stress gradient method, and the effective distances are decreased with the decrease of notch radius for the same strain path. The fatigue life is predicted based on the strain at the effective distance, and the predictions are scattered and unconservative. Combining the test results and simulations, a new method determinating the effective distance is presented considering the strain gradient. Most prediction results are in a factor-2 scatter band.