Study on the Characteristic Stress-Life Curve of Different Materials and Failure Modes

The effective flaw model is developed to describe the S-N curves of different materials and failure modes. By introducing the concepts of the “equivalent static loading” and the “equivalent number of cycles,” a new data fitting technique suggested by the present paper has some physical meaning. Using the simplified form of the present characterization, only a few tests are required to describe the sketch of unknown material S-N curve under the fatigue loading.