The interaction between point defects and edge dislocation in bcc iron
The authors present results of atomistic simulations of the interaction between self interstitial atoms and vacancies with edge dislocations in BCC iron. The calculations are carried out using molecular dynamics with an energy minimization scheme based on the quasi-Newton approach and use the Finnish-Sinclair interatomic potential for BCC iron developed by Ackland et al. large anisotropy in the strain field of self interstitials is observed and it causes strong interaction with edge dislocations even when the defect is located on the dislocation glide plane. For vacancies, the relaxation volume is smaller and much more isotropic, which results in a far weaker interaction with the dislocation. A temperature dependent capture radius for vacancies and self interstitials is extracted from the simulations. The difference between the capture radii of vacancies and self interstitials is used to define the sink strength of the dislocation. Large deviations are observed from the predictions of elasticity based on treating point defects as isotropic dilatational centers. Further, the capture radius of edge dislocations in BCC iron is observed to be small and is of the order of 1--3 nm for self interstitials.
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- W-7405-ENG-48
- OSTI ID:
- 345080
- Report Number(s):
- CONF-980902--
- Journal Information:
- Journal of Engineering Materials and Technology, Journal Name: Journal of Engineering Materials and Technology Journal Issue: 2 Vol. 121; ISSN 0094-4289; ISSN JEMTA8
- Country of Publication:
- United States
- Language:
- English
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