Fatigue Limit Diagrams and Fatigue Life Prediction Models for Metallic Materials and Welded Details: A Review

ABSTRACT

The fatigue limit and fatigue life vary depending on the loading mode and are also greatly affected by stress concentration. The effect of mean stress has been mathematically expressed using several models, but based on experimental data, the Walker model is the most appropriate. Although the model constants differ depending on the material, stress concentration state, and loading mode, it was shown that high prediction accuracy can be achieved by selecting appropriate constants for both smooth and notched specimens. The same was true for the effect of assembling stress due to welding distortion on the fatigue limit and the threshold stress intensity range of welded details. Furthermore, it was shown that this model can also be applied to predicting multiaxial fatigue and to estimating statistical failure probability. By using the concept of equivalent alternating stress, it became possible to apply the Walker model to predict both the fatigue limit and the fatigue life under arbitrary stresses in the high‐cycle regime.