抄録
Various models for the elasto-plastic behavior with the complex hardening of a metal under the multi-axial cyclic loading have been proposed before. Especially, the sub-layer model and the multi-surface model are well-known. The former is clearer to understand the mechanism of the complex hardening than the latter because the various assumptions are used in the multi-surface models. However, the sub-layer model is not suitable to apply to structure models with huge number of elements because it is much more costly. Then, we suggested the convenient model for uni-axial stress field which was led from the sub-layer model through the thermodynamic approach and shown the model was successful for our object by using numerical results. In this paper, we extend our model to the elasto-plastic problem in the multi-axial stress field. For the sake, some approximation equations are used in the present extension. The validity of these approximations and the effectiveness of our model are shown through numerical results.
