Fatigue Crack-Growth Resistance of Thermally Hardened 65G Steel Under Transverse Shear

摘要

We plot the kinetic diagrams of fatigue fracture of 65G steel under the conditions of transverse shear after different modes of heat treatment within the range of fatigue crack-growth rates covering six orders of magnitude with the use of the stress intensity factor for the evaluation of the stress-strain state in the vicinity of the crack tip. The main and auxiliary characteristics of cyclic crack-growth resistance are determined with regard for the friction of the lips of a fatigue crack. We construct the diagrams of structural strength and confirm the hypothesis that the fatigue thresholds increase with the yield strength of 65G steel under the conditions of shear.