New cyclic crystal viscoplasticity model based on combined nonlinear kinematic hardening for single crystals

摘要

Based on the existing experimental data of cyclic deformation for copper single crystal, a facencentred cubic crystal, a new cyclic constitutive model was developed in the framework of singlencrystal viscoplasticity. In the developed model, a combined nonlinear kinematic hardening modelnwas introduced and the remarkable cyclic hardening of copper single crystal was described bynthe progressive evolution of back stress and isotropic deformation resistance in each slip system.nThe self- and latent-hardening of dislocation slip in the different slip systems were considered bynemploying an interaction hardening matrix H. The proposed model is first verified by comparingnthe simulated results with some referable experimental data. And then, the capability of the modelnto describe the uniaxial ratcheting of copper single crystal is discussed, even if the correspondingnexperimental data cannot be referred now yet.