Atomistic modeling of carbon Cottrell atmospheres in bcc iron

Autor(es)

Veiga, R. G. A. ^{[1, 2]} ; Perez, M. ^[2] ; Becquart, C. S. ^[3] ; Domain, C. ^[4]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Escola Politecn, Dept Engn Met & Mat, BR-05508030 Sao Paulo - Brazil

^[2] Univ Lyon, INSA Lyon, Lab MATEIS, CNRS, UMR 5510, F-69621 Villeurbanne - France

^[3] Ecole Natl Super Chim Lille, UMET, CNRS, UMR 8207, F-59655 Villeneuve Dascq - France

^[4] EDF, F-77250 Moret Sur Loing - France

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF PHYSICS-CONDENSED MATTER; v. 25, n. 2 JAN 16 2013.
• Citações Web of Science: 21

Resumo

Atomistic simulations with an EAM interatomic potential were used to evaluate carbon-dislocation binding energies in bcc iron. These binding energies were then used to calculate the occupation probability of interstitial sites in the vicinity of an edge and a screw dislocation. The saturation concentration due to carbon-carbon interactions was also estimated by atomistic simulations in the dislocation core and taken as an upper limit for carbon concentration in a Cottrell atmosphere. We obtained a maximum concentration of 10 +/- 1 at.% C at T = 0 K within a radius of 1 nm from the dislocation lines. The spatial carbon distributions around the line defects revealed that the Cottrell atmosphere associated with an edge dislocation is denser than that around a screw dislocation, in contrast with the predictions of the classical model of Cochardt and colleagues. Moreover, the present Cottrell atmosphere model is in reasonable quantitative accord with the three-dimensional atom probe data available in the literature. (AU)

• Processo FAPESP: 11/19564-6 - Modelagem computacional da evolução microestrutural de ligas Fe-Ni-C
• Beneficiário: Roberto Gomes de Aguiar Veiga
• Linha de fomento: Bolsas no Brasil - Pós-Doutorado