A Review of Fatigue Life Prediction Methods

Fatigue lives are predicted by a variety of methods, including stress-life curves, local stresses and strains, fracture mechanics, and service simulation tests. These approaches are reviewed as to their advantages and disadvantages, and also as to their relationships with one another and their place in the design process. Life prediction for variable amplitude service-type load histories is considered in some detail. It is concluded that it is important to apply appropriate cycle counting and to account for interactions among high and low stresses. It is suggested that life predictions which consider both crack initiation and crack growth are often appropriate.