Critical grain size for dislocation storage and consequences for strain hardening of nanocrystalline materials

We consider strain hardening of nanostructured materials and propose a physically based interpretation of their low strain hardening capability in terms of a reduced storage rate of dislocations The model suggested provides a modification of the Kocks-Mecking-Estrin evolution law for dislocation storage for nanostructured materials and predicts a critical grain size below which the strain hardening rate drops off (C) 2010 Published by Elsevier Ltd on behalf of Acta Materialia Inc