Dynamic properties of edge dislocations decorated by interstitial dislocation loops in alpha-iron and copper.
- ORNL
- University of Liverpool
- Riso National Laboratory, Roskilde, Denmark
Clusters of self-interstitial atoms (SIAs) in the form of parallel crowdions are created directly in high-energy displacement cascades produced in metals by neutron irradiation. They are equivalent to small perfect dislocation loops and, in isolation in pure metals, undergo fast thermally-activated glide in the direction of their Burgers vector. Their strain field and ability to glide allows long-range interaction with other extended defects. Indeed, dislocations decorated by dislocation loops are commonly observed after neutron irradiation. Dislocations gliding under applied stress also encounter these mobile defects. These effects influence mechanical properties and require further investigation. This paper presents results from an atomic-scale study of copper and {alpha}-iron at either 0 K or 300 K. Loop drag and breakaway effects are investigated for an edge dislocation under applied stress interacting with a row of SIA loops below its glide plane. The maximum speed at which a loop is dragged is lower in copper than iron, and the applied stress at which this occurs is also lower. These differences in the dynamics of cluster-dislocation interaction are determined by the atomic structure of the defects and cannot be investigated by continuum treatment.
- Research Organization:
- Oak Ridge National Laboratory (ORNL)
- Sponsoring Organization:
- SC USDOE - Office of Science (SC)
- DOE Contract Number:
- AC05-00OR22725
- OSTI ID:
- 1003349
- Journal Information:
- Philosophical Magazine Letters, Journal Name: Philosophical Magazine Letters Journal Issue: 11 Vol. 85; ISSN 0950-0839
- Country of Publication:
- United States
- Language:
- English
Similar Records
A Model for the Dynamics of Loop Drag by a Gliding Dislocation.
Simulation of the interaction between an edge dislocation and a ⟨1 0 0⟩ interstitial dislocation loop in α-iron