2021 年 62 巻 8 号 p. 1124-1132
In the present study, crystal plasticity models applicable for reproducing the work-hardening behavior under various loading paths of an A5083-O Al alloy sheet were examined. The loading paths under consideration were tension, reverse loading from compression to tension, simple shear, and biaxial tension. The accumulated-slip-based hardening model with the extended Voce hardening law provided good predictive accuracy for work-hardening behavior under uniaxial loadings. In contrast, it could not reproduce anisotropic hardening under biaxial tension, which was observed in the experimental results. In the case of dislocation-density-based hardening models, the work-hardening behavior under both uniaxial loadings and biaxial tension was reproduced fairly well when an anisotropic property in the interaction matrix was considered. On the basis of these results, a new accumulated-slip-based hardening model was proposed, in which the effects of latent hardening were considered in calculation of accumulated slip. The new model allowed prediction of anisotropic hardening under biaxial tension as in the case of the dislocation-density-based hardening model. This result suggested that the predictive accuracy of anisotropic hardening was more affected by the modelling of the latent hardening and interaction matrix than by the choice of internal variables of hardening, i.e., accumulated slip or dislocation density.
