Abstract
The effects of overload on the fatigue limit and threshold stress intensity factor range (Δkth) of SUS316 were studied. Tensile or compressive overload were applied to the bending fatigue test specimens with a small crack-like surface defect and fatigue tests were carried out to determine the fatigue limit and Δkth. It was found that the Δkth increased by tensile overloading. The increasing rate of Δkth in the CT specimen is larger than that in the bending fatigue test specimen with a small crack-like surface defect. Thus, the crack size effects on the improvement of Δkth after overloading were observed. The results are discussed from the viewpoint of fracture mechanics.
