Large-strain hardening curves corrected for texture development

The paper is concerned with the problem of constructing equivalent stress-e quivalent strain curves at large strains. For the equivalent strain, the av erage accumulated crystallographic shear is used, while for the equivalent stress, the resolved shear stress is employed. The latter is obtained from the work conjugacy condition. In such a construction of the hardening curve , the Taylor factor appears to be the major factor that can be calculated f rom polycrystal deformation texture models. In this paper, the viscoplastic Taylor and self-consistent approaches are employed to calculate the Taylor factors. The self-consistent model was calibrated on the torsion texture d evelopment which is the most sensitive to the polycrystal model parameters at large strains. The obtained Taylor factors show important variations in torsion, compression and rolling. They have been used to convert experiment ally measured work hardening data on copper into resolved shear stress-reso lved shear strain curves. The effect of the Taylor factor on the absolute h ardening rate was found to be significant at a large strain range of deform ation. The simulation textures were markedly different from the measured te xtures at very large strains where both polycrystal texture deformation mod els fail to predict the correct texture evolution. For this reason, the tex tures were measured at increasing strains at 11 points in rolling, at 12 po ints in compression and at four points in torsion from where the Taylor fac tors were calculated by both of the models in order to construct the equiva lent stress-equivalent strain curves.