スプリットホプキンソン棒型衝撃引張り試験法における降伏現象

抄録

To identify the yielding phenomena often observed in tensile test at high strain rates even for the constitutive equation of material without any yielding phenomena, numerical simulations using the dynamic FEM analysis have been performed to study the effect of specimen geometry and loading configurations in the Split-Hopkinson Pressure Bar apparatus. Stress distributions in the specimens and the loading bars are clarified, and it is found that the three-dimensional stress wave propagation from the specimen to the loading bar dominates the yielding phenomena due to radial oscillations associated with, even though a slight effect of the specimen geometry is involved to some extent. It is also found that the relevant shape of loading bar end is served to suppress the yielding phenomena.