Procedure for Estimating Bending and Torsional Fatigue Strength of Smooth Specimens on Criteria of Axial-Load Fatigue Strength Diagrams

Abstract

The equivalent cyclic stress ratio REQ followed by elastic-completely plastic yield zone partition type cross-section dimension dependence magnification factor, which is modified to fatigue strength criterion specification, is applied to estimation of plane bending fatigue strength of a smooth bar with rectangular, circular and rhombic cross-section, and rotating bending and torsion fatigue strength of a round smooth bar from an axial load fatigue strength diagram of a smooth specimen. This approach is expected to be effective in elucidating the size effect and its material dependence.