Investigation of Grade 45 steel under Low Cycle Tension-Compression and Torsion

The investigation results of low cycle strength and fatigue life of grade 45 steel under symmetrical (r = -1.0) tension-compression and torsion and asymmetrical (r = -0.75, -0.5) torsion are presented. Used testing technique and parameters of the stress strain curves and lifetime are given. The shear stress strain was analysed using the solid specimens of circular cross-section and it was determined, that influence of the stress gradient is non significant, if compared with the analysis of thin-walled tube specimens. Proposed analytical dependences for determination torsion strength and fracture parameters using tension-compression results. Proposed new method for calculation torsion fatigue life using tension-compression data. Theoretical conclusions was verified with experiments, which were performed with author's designed devices.