Fatigue Life Prediction Considering Constraint of Notches

A fatigue life prediction procedure was discussed from the viewpoint of the constraint effect of notches. In this report, fatigue crack initiation lives were used to avoid the fatigue crack propagation process and the prediction procedure was examined experimentally. It was fouud that fatigue crack initiation lives depend on the local strain amplitude at the notch root, and the constraint effect of notches to fatigue crack initiation lives may be considered as the multiaxial effect at the notch root and might be evaluated through the equivalent stress concept as used in the multiaxial fatigue problem. The experimental results showed good agreement with the proposed fatigue life prediction procedure.