面内異方性降伏条件の実験的考察 : 第2報,降伏曲線および相当応力-相当ひずみ曲線 An Experimental Investigation of Yield Criteria with Planar Anisotropy : 2nd Report, Yield Loci and Equivalent Stress-Strain Curves

In addition to uniaxial tension and through-thickness compression reported in the previous paper, commercial-purity aluminium and deep-drawing-quality steel sheets are tested in plane-strain compression and simple shear. The yield loci and the equivalent stress-strain flow curves based on Hill's 1948 quadratic, Hil1's 1990 nonquadratic and Gotoh's biquadratic criteria are obtained on the basis of equal amounts of plastic work. The yield loci calculated from Hill's quadratic criterion for case (2) in which the anisotropic parameters are mainly determined with yield stresses and Gotoh's biquadratic criterion are close to each other and provide fairly good fits to the experiments except for the annealed aluminium. Hill's theories for case (2) are also found to be rather reasonable for all the materials used here when the flow curves are compared with each other.