Since the rigid body rotation can be clearly removed from the shearing strain component, and the additive law of strain can be satisfied, the Natural Strain is effective strain representation for expressing the stress-strain behavior under large elasto-plastic deformation. Based on the Natural Strain theory, the purpose of this study is to clarify the mechanism of development of anisotropy in the yield surface that occurs with the progression of deformation by examining the shape of yield surface obtained under large deformation. In our previous studies, using test pieces that the large pre-deformation of uniaxial tension, simple shear and the proportional loading of them are applied, proportional loading tests are carried out again by changing the ratio of tension and shear. In the present paper, another type of the pre-deformation that the deformation path is different but the final deformation state is the same as the predeformation of proportional loading of tension and shear, is chosen as the subject of this study. In particular, the deformation history of tension after simple shear is examined in this study. Then, the relationship between the development of anisotropy in yield surface and the deformation history is revealed in this paper.
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