An investigation of the prediction accuracy for volume based HCF models using scaled geometries and scaled loading

• The prediction accuracy for volume based HCF models is investigated.
• Specimens scaled in size with the same stress at corresponding scaled points are used.
• The V∗V∗-model provides the most accurate HCF prediction at low stress levels.
• The V∗V∗-model is favored for HCF design purposes.

The prediction accuracy for the volume based Weibull- and V∗V∗ high cycle fatigue models is investigated and compared to the point method. A high number of fatigue tests are performed in rotating bending for single notched cylindrical specimens manufactured in a 12% Cr-steel, a high quality structural steel. The specimens are designed with different highly stressed volume and stress gradient by scaling the geometry, but with the same stresses at the corresponding scaled points. Thus, the maximum stress in the notch is the same. Experiments are performed for three specimen sizes at several stress levels. The volume based Weibull- and V∗V∗-models, as well as the point stress method are fitted to the experimental results. Based on the results, the V∗V∗-model is favored for design purposes.