Simulation of the interaction between an edge dislocation and a 〈1 0 0〉 interstitial dislocation loop in α-iron

TY - JOUR

T1 - Simulation of the interaction between an edge dislocation and a 〈1 0 0〉 interstitial dislocation loop in α-iron

AU - Terentyev, D.

AU - Grammatikopoulos, P.

AU - Bacon, D. J.

AU - Osetsky, Yu N.

N1 - Funding Information: This work was performed in the framework of the 7th Framework Programme collaborative project GETMAT, partially supported by the European Commission, Grant Agreement No. 212175. It was also supported by grant GR/S81162/01 from the UK Engineering and Physical Sciences Research Council; grant F160-CT-2003-508840 (“PERFECT”) under programme EURATOM FP-6 of the European Commission; and partly by the Division of Materials Sciences and Engineering and the Office of Fusion Energy Sciences, US Department of Energy, under contract DE-AC05-00OR22725 with UT-Battelle, LLC.

PY - 2008/10

Y1 - 2008/10

N2 - Atomic-level simulations are used to investigate the interaction of an edge dislocation with 〈1 0 0〉 interstitial dislocation loops in α-iron at 300 K. Dislocation reactions are studied systematically for different loop positions and Burgers vector orientations, and results are compared for two different interatomic potentials. Reactions are wide-ranging and complex, but can be described in terms of conventional dislocation reactions in which Burgers vector is conserved. The fraction of interstitials left behind after dislocation breakaway varies from 25 to 100%. The nature of the reactions requiring high applied stress for breakaway is identified. The obstacle strengths of 〈1 0 0〉 loops, 1/2〈1 1 1〉 loops and voids containing the same number (169) of point defects are compared. 〈1 0 0〉 loops with Burgers vector parallel to the dislocation glide plane are slightly stronger than 〈1 0 0〉 and 1/2〈1 1 1〉 loops with inclined Burgers vector: voids are about 30% weaker than the stronger loops. However, small voids are stronger than small 1/2〈1 1 1〉 loops. The complexity of some reactions and the variety of obstacle strengths poses a challenge for the development of continuum models of dislocation behaviour in irradiated iron.

AB - Atomic-level simulations are used to investigate the interaction of an edge dislocation with 〈1 0 0〉 interstitial dislocation loops in α-iron at 300 K. Dislocation reactions are studied systematically for different loop positions and Burgers vector orientations, and results are compared for two different interatomic potentials. Reactions are wide-ranging and complex, but can be described in terms of conventional dislocation reactions in which Burgers vector is conserved. The fraction of interstitials left behind after dislocation breakaway varies from 25 to 100%. The nature of the reactions requiring high applied stress for breakaway is identified. The obstacle strengths of 〈1 0 0〉 loops, 1/2〈1 1 1〉 loops and voids containing the same number (169) of point defects are compared. 〈1 0 0〉 loops with Burgers vector parallel to the dislocation glide plane are slightly stronger than 〈1 0 0〉 and 1/2〈1 1 1〉 loops with inclined Burgers vector: voids are about 30% weaker than the stronger loops. However, small voids are stronger than small 1/2〈1 1 1〉 loops. The complexity of some reactions and the variety of obstacle strengths poses a challenge for the development of continuum models of dislocation behaviour in irradiated iron.

KW - Dislocation loop

KW - Edge dislocation

KW - Iron

KW - Molecular dynamics

UR - http://www.scopus.com/inward/record.url?scp=53049103248&partnerID=8YFLogxK

U2 - 10.1016/j.actamat.2008.06.032

DO - 10.1016/j.actamat.2008.06.032

M3 - 文章

AN - SCOPUS:53049103248

SN - 1359-6454

VL - 56

SP - 5034

EP - 5046

JO - Acta Materialia

JF - Acta Materialia

IS - 18

ER -