Distortional and orientational hardening at large viscoplastic deformations

Distortional and orientational hardening, reflecting macroscopically texture development, are combined with standard isotropic and kinematic hardening features in the development of a constitutive model for large viscoplastic deformations of metals. The proper choice of hardening parameters, including those for plastic spin expressions within a multiple spins formulation, allows the realistic simulation of data from fixed-end torsion experiments, in which the axial stress oscillates or changes sign while the shear stress increases monotonically. The model response is examined under reverse loading and different rates and temperatures. Copyright (C) 1996 Elsevier Science Ltd