Prediction of the behavior of small fatigue cracks

A modified linear-elastic fracture mechanics approach has been proposed and developed by McEvily and co-workers, with which the fatigue crack growth rates of both small cracks and large cracks can be quantitatively evaluated. This paper reviews the recent results of applications of this approach to the following fatigue problems involving the prediction of the behavior of small fatigue cracks: (1) in an examination of the use of Miner's rule in fatigue life estimation under variable amplitude loading, (2) in the verification of the area parameter model, and (3) in the prediction of the fatigue life and strength of defect-containing components subjected to multiaxial stress.