aFaculty of Aerospace Engineering, Delft University of Technology, Kluyverweg 1, 2629 HS, Delft, The Netherlands;bArcelorMittal Research, Voie Romaine-BP30320, 57283 Maizières-lès-Metz Cedex, France
Abstract:
The present work extends a recent model for plastic deformation of polycrystalline metals based on irreversible thermodynamics. A general dislocation evolution equation is derived for a wide range of strain rates. It is found that there is a transitional strain rate (103 s−1) over which the phonon drag effects play a dominant role in dislocation generation resulting in a significant raise in the dislocation density and flow stress. The model reduces to the classical Kocks–Mecking model at low strain rates.