Dislocation core reconstruction induced by carbon segregation in bcc iron - CNRS - Centre national de la recherche scientifique Accéder directement au contenu
Article Dans Une Revue Physical Review B: Condensed Matter and Materials Physics (1998-2015) Année : 2015

Dislocation core reconstruction induced by carbon segregation in bcc iron

Résumé

The relative stability of dislocation core configurations in body-centered-cubic metals is profoundly modified by the presence of solutes. Considering the Fe(C) system, we demonstrate by using density functional theory that carbon atoms destabilize the usual easy core to the benefit of the hard core configuration of the screw dislocation, which is unstable in pure metals. The carbon atom is at the center of a regular prism in a cementitelike local environment. The same dislocation core reconstruction is also found with other solutes (B, N, O) and in W(C). This unexpected low-energy configuration induces a strong solute-dislocation attraction, leading to dislocation core saturation by solute atoms, even for very low bulk solute concentrations. This core reconstruction will constitute an essential factor to account for in solute-segregation related phenomena, such as strain aging.

Mots clés

Fichier principal
Vignette du fichier
a468ab9f2822688c12a754ffcf309ce83311.pdf (339.29 Ko) Télécharger le fichier
Origine : Fichiers éditeurs autorisés sur une archive ouverte

Dates et versions

hal-02305589 , version 1 (03-02-2021)

Identifiants

Citer

Lisa Ventelon, B. L. Uethi, E. Clouet, L. Proville, B. Legrand, et al.. Dislocation core reconstruction induced by carbon segregation in bcc iron. Physical Review B: Condensed Matter and Materials Physics (1998-2015), 2015, 91 (22), pp.220102. ⟨10.1103/PhysRevB.91.220102⟩. ⟨hal-02305589⟩
71 Consultations
221 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More