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

Journal Article · Wed Oct 01 04:00:00 EDT 2008 · Acta Materialia

DOI:https://doi.org/10.1016/j.actamat.2008.06.032· OSTI ID:1049840

Terentyev, Dmitry ^[1]; Grammatikopoulos, P. ^[2]; Bacon, David J. ^[2]; Osetskiy, Yury N. ^[3]

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1. Belgian Nuclear Research Centre, SCK-CEN
2. University of Liverpool, UK
3. ORNL

Atomic-level simulations are used to investigate the interaction of an edge dislocation with ⟨100⟩ 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 ⟨100⟩ loops, 1/2 ⟨111⟩ loops and voids containing the same number (169) of point defects are compared. ⟨100⟩ loops with Burgers vector parallel to the dislocation glide plane are slightly stronger than ⟨100⟩ and 1/2 ⟨111⟩ loops with inclined Burgers vector: voids are about 30% weaker than the stronger loops. However, small voids are stronger than small 1/2 ⟨111⟩ 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.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 1049840
• Journal Information: Acta Materialia, Journal Name: Acta Materialia Journal Issue: 18 Vol. 56; ISSN 1359-6454; ISSN ACMAFD
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BURGERS VECTOR
DISLOCATIONS
EDGE DISLOCATIONS
INTERSTITIALS
IRON
POINT DEFECTS
SIMULATION