銅の繰返し硬化挙動の結晶塑性的数値シミュレーション

抄録

The constitutive equation for analyzing the cyclic deformation was developed by introducing the concept of the internal stress and the dislocation multiplication into the Johnston-Gilman's equation modified by the authors. Then, the numerical simulation of the cyclic stress-strain hysteresis loop accompanied by the cyclic straining was done for the annealed copper. The stress and plastic strain ranges estimated were slightly different from the test results in the transition hardening stage under the total strain range-controlled condition. Meanwhile, the former was in good agreement with the latter in the saturation hardening stage, where the cyclic mechanical properties of materials were commonly represented in the practical use. The analyzed hysteresis loop tends to be fatter in shape than the experimental one at the larger strain range controlled in the test. This problem, however, is solved by adjusting one of the parameters included in the proposed constitutive equation, which are determined by the static tensile and stress-relaxation tests.