Abstract
In the previous report, using the Natural Strain theory, the shape of yield surface and the distribution of the strain hardening modulus h around the yield surface have been examined by conducting the proportional loading tests for tension and torsion after giving the pre-deformation of uni-axial tension to the test pieces. In this paper, the shape of the yield surface, which is obtained after giving the pre-deformation of large simple shear, is estimated by examining the strain hardening modulus h in various directions in the stress space. Especially, the development of anisotropy for the shape of the yield surface is examined by changing the direction of the pre-deformation of simple shear. Moreover, the yield surface estimated by investigating the strain hardening modulus h for various directions in the stress space is compared with the shape of yield surface obtained by the conventional proof stress.
