| Titre : | Plastic deformation of wadsleyite : IV Dislocation core modelling based on the Peierls–Nabarro–Galerkin model (2011) |
| Auteurs : | Arnaud Metsue, Auteur ; Philippe Carrez, Auteur ; Christophe Denoual, Auteur |
| Type de document : | Article : texte imprimé |
| Dans : | Acta materialia (Vol. 58 N° 5, Mars 2010) |
| Article en page(s) : | pp. 1467–1478 |
| Note générale : | Métallurgie |
| Langues : | Anglais |
| Tags : | Wadsleyite Dislocations Modelling Peierls–Nabarro Element-free Galerkin |
| Résumé : | In this paper, we determine dislocation core structures and Peierls stresses of wadsleyite, a high-pressure mineral present in the Earth mantle. We use a Peierls–Nabarro model combined with a finite-element method in which we introduce two-dimensional generalized stacking fault energies. Several potential slip planes of wadsleyite are considered. The results show that dislocations in this mineral can exhibit complex dislocation cores with linear or non-collinear dissociation and even three-dimensional dislocation cores. The calculation of the Peierls stresses gives information on the potential activity of slip systems governing the plasticity of wadsleyite. Our study confirms experimental observations that ½〈1 1 1〉{1 0 1} is the easiest slip system in this structure at high-pressure and that [1 0 0](0 1 0) is the second easiest. Both these easily slip systems have dislocations that dissociate into collinear partial dislocations. In contrast [0 1 0] dislocations with very large Burgers vector (11.2 Å) are stabilized by complex dissociations involving four partial dislocations. |
| DEWEY : | 669 |
| ISSN : | 1359-6454 |
| En ligne : | http://www.sciencedirect.com/science/article/pii/S1359645409007502 |
