Fatigue analysis for crack initiation

Abstract

For the prediction of life leading to fatigue crack initiation, a method for performing a cycle‐by‐cycle local stress analysis at the stress concentration area of a structural component was developed. Elastoplastic stress‐strain values along the hysteresis loop are traced for each load reversal in making the life prediction calculations. In this manner, the load sequence effect and the residual stress due to local yielding are inherently included. Neuber's rule and a linear rule were used with this method and compared. The results of life prediction were compared with test results. The use of the linear rule provided more accurate predictions than using other alternatives, including Miner's rule.