Texture dependent plastic behavior of Zr 702 at large strain

Three polycrystalline samples of Zr702 alpha are deformed at room temperature under channel die compression until about 40% strain. Samples are oriented differently in the die with respect to their texture, so that the influence of the initial texture on the stress-strain response, the activated deformation systems, and the subsequent texture evolution can be assessed. Experimental results are interpreted by using a viscoplastic self-consistent (VPSC) polycrystalline model in which a saturating anisotropic intracrystalline hardening law is introduced, It is shown that the orientation dependence of the activated slip systems strongly depends on the texture of the polycrystal. The main effect of intracrystalline hardening is found to be a redistribution of slip from the primary to the secondary systems, but in a moderate way such that it does not affect significantly the development of texture. A simple analysis shows that the increasing activity of the secondary slip systems can be assessed directly from the macroscopic stress-strain curves. (C) 2001 Elsevier Science B.V. All rights reserved.