Interpretation of unloading tests on nanocrystalline Cu in terms of two mechanisms of deformation

Hu et al. [1] reported the strains measured during unloading of nanocrystalline Cu in the course of deformation at room temperature. The inelastic strain rates during unloading are found to be larger than the quasi-stationary rates. This remarkable result is interpreted in terms of recovery strain acting as a second deformation mechanism in addition to the primary mechanism of glide of free dislocations.