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

Olivier Bouaziz (1, 2) , Y. Estrin (3, 4) , Yves Brechet (5) , J.D. Embury (6)

1 ArcelorMittal Maizières Research SA
2 MAT - Centre des Matériaux
3 ARC Centre of Excellence for Design in Light Metals
4 CSIRO Division of Materials Science and Engineering
5 SIMaP - Science et Ingénierie des Matériaux et Procédés
6 McMaster University [Hamilton, Ontario]

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.

Mots clés: Strain hardening; Nanostructure; Dislocations; Diffusion

Domaines: Sciences de l'ingénieur [physics]; Matériaux

Olivier Bouaziz, Y. Estrin, Yves Brechet, J.D. Embury. Critical grain size for dislocation storage and consequences for strain hardening of nanocrystalline materials. Scripta Materialia, 2010, 63, pp.477-479. ⟨10.1016/j.scriptamat.2010.05.006⟩. ⟨hal-00509787⟩