First principles calculations of vacancy–vacancy interactions in nickel: thermal expansion effects - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Journal of Physics: Condensed Matter Année : 2010

First principles calculations of vacancy–vacancy interactions in nickel: thermal expansion effects

Résumé

The energetic properties of the divacancy defect in fcc nickel are studied by ab initio calculations based on density functional theory. The formation and binding enthalpies of the divacancy in the first (1nn), second (2nn) and third (3nn) nearest-neighbor configurations are presented. Results show that the 1nn divacancy configuration is the most stable with a formation enthalpy H2vf of 2.71 eV and a small binding energy H2vb of 0.03 eV. In the 2nn configuration, the monovacancy–monovacancy interaction is repulsive, and it vanishes in the 3nn configuration. The migration process of the divacancy in its stable configuration is studied. We find that the divacancy migrates in the (111) plane by successive rotational steps of 60°. The corresponding migration enthalpy H2vm is predicted to be 0.59 eV, about half of that found for the monovacancy. For a better comparison of our results with high temperature experimental data, we have analyzed the effects of thermal expansion. Our results show that the inclusion of thermal expansion allows us to reproduce satisfactorily the experimental predictions.

Mots clés

Fichier principal
Vignette du fichier
Megchiche_4715.pdf (411.84 Ko) Télécharger le fichier
Origine Fichiers produits par l'(les) auteur(s)

Dates et versions

hal-03550662 , version 1 (01-02-2022)

Identifiants

Citer

El Hocine Megchiche, Claude Mijoule, Mohand Amarouche. First principles calculations of vacancy–vacancy interactions in nickel: thermal expansion effects. Journal of Physics: Condensed Matter, 2010, 22 (48), pp.0. ⟨10.1088/0953-8984/22/48/485502⟩. ⟨hal-03550662⟩
4 Consultations
9 Téléchargements

Altmetric

Partager

Gmail Mastodon Facebook X LinkedIn More