摘要

The quasi-static standard tensile, torsional, and combined tension and torsion tests were performed at room temperature to investigate the mechanical properties of normalized AISI 1045 steel specimens. The performance of yielding, Young's modulus, and modulus of elasticity in shear were analyzed via two kinds of experiments with sequence-given loading paths, such as tension-torsion (torsional response after tension) and torsion-tension (tensile response after torsion) tests, under various preloads. Additionally, time-variant coupled effects between the shear stress and normal stress responded similarly in tension-torsion and torsion-tension experiments. Results demonstrate that ultimate strengths of torsion and tension obtained by combined tension and torsion tests were consistent with those strengths achieved by standard uniaxial tests. Yield strengths derived by the Von Mises criterion and combined tension and torsion test were compared, and results showed maximum deviations of 23.01% and 43.28% in shear and normal stress, respectively. Results indicated that the material exhibited quite different mechanical properties under combined loads of tension and torsion from those under uniaxial loads.