Behaviour of Polycrystalline Metals at Large Plastic Strains

Abstract

Recent work by the author and collaborators on the plastic behaviour of polycrystalline metals at large strains is reviewed. The crystal plasticity constitutive relations used in the analytical and numerical simulations are first briefly presented. The particular formulation adopted assumes rate-dependent crystallographic slip. We then report some special results where, for FCC crystals with certain "ideal textures", exact closed-form analytical solutions have been obtained for a variety of deformation modes. The implementation of the crystal plasticity constitutive relations in the finite-element analysis of large strain metal deformation processes is then considered. Finally, we discuss current experimental work in our laboratory regarding the determination of yield surfaces for thin sheet metals, and the characterization of the stress-strain response of these materials under complex histories of biaxial deformation.