Disconnections kinks and competing modes in shear-coupled grain boundary migration - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Physical Review B: Condensed Matter and Materials Physics (1998-2015) Année : 2016

Disconnections kinks and competing modes in shear-coupled grain boundary migration

Nicolas Combe
Marc Legros

Résumé

The response of small-grained metals to mechanical stress is investigated by a theoretical study of the elementary mechanisms occurring during the shear-coupled migration of grain boundaries (GB). Investigating a model Σ17(410) GB in a copper bicrystal, both (110) and (100) GB migration modes are studied focusing on both the structural and energetic characteristics. The minimum energy paths of these shear-coupled GB migrations are computed using the nudge elastic band method. For both modes, the GB migration occurs through the nucleation and motion of disconnections. However, the atomic mechanisms of both modes qualitatively differ: While the (110) mode presents no metastable state, the (100) mode shows multiple metastable states, some of them evidencing some kinks along the disconnection lines. Disconnection kinks nucleation and motion activation energies are evaluated. Besides, the activation energies of the (100) mode are smaller than those of the (110) one except for very high stresses. These results significantly improve our knowledge of the GB migration mechanisms and the conditions under which they occur.
Fichier principal
Vignette du fichier
PhysRevB.93.024109.pdf (485.92 Ko) Télécharger le fichier
Origine : Fichiers éditeurs autorisés sur une archive ouverte
Loading...

Dates et versions

hal-01729242 , version 1 (12-03-2018)

Identifiants

Citer

Nicolas Combe, Frédéric Mompiou, Marc Legros. Disconnections kinks and competing modes in shear-coupled grain boundary migration. Physical Review B: Condensed Matter and Materials Physics (1998-2015), 2016, 93 (2), pp.024109. ⟨10.1103/PhysRevB.93.024109⟩. ⟨hal-01729242⟩
385 Consultations
155 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More