Development of Fatigue Limit Analysis Diagram: FLAD was conducted to estimate the fatigue limit of materials with a surface defect like a surface flaw. To make the FLAD, new criterion of cyclic plastic zone, based on Dugdale model, and cyclic Crack Tip Opening Displacement: CTOD, were proposed. The FLAD in this study considers the effect of stress ratio. Therefore, assuming the residual stress as the stress ratio, the shot peening effect was considered. The FLAD using new criterion was compared with literature data. As a result, the proposed FLAD concurred with experimental data despite differences in materials and stress ratios.
