Assistant professor, South Dakota School of Mines and Technology, Rapid City, S. D.
A means to determine the fatigue notch factor, Kf is devised by identifying the zone of metal at the notch root which is thought to govern the fatigue process. Corrections are then developed for the effects of the stress gradient and critical volume in this zone. The resulting equation for Kf embodies these corrections and the theoretical elastic stress concentration factor, Kt. Experimental verification is obtained by testing notched plate specimens and by utilizing data from the literature. Predictions of Kf over fatigue lives of from 102 to 106 cycles are within 4 percent of experimental values when calculated in terms of stress and within 9 percent in terms of strain.
Paper ID: JTE10038J