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Title: On the features of dislocation-obstacle interactions in thin films: direct comparison between in situ experiments and large scale computer modeling.

Abstract

Large-scale atomistic modelling has demonstrated that the dynamic interactions of dislocations in thin films have a number of remarkable features. A particular example is the interaction between a screw dislocation and a stacking fault tetrahedron (SFT) in Cu, which can be directly compared with in situ observations of quenched or irradiated fcc metals. If the specimen is thin, the dislocation velocity is slow, and the temperature is high enough, a segment of the original SFT can be transported towards the surface via a double cross-slip mechanism and fast glide of an edge dislocation segment formed during the interaction. The mechanisms observed in the simulations provide an explanation for the results of in situ straining experiments and the differences between bulk and thin film experiments.

Authors:
 [1];  [1];  [1];  [1]
  1. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
958749
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Philosophical Magazine Letters; Journal Volume: 86; Journal Issue: 8
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; COMPUTERS; DISLOCATIONS; EDGE DISLOCATIONS; SCREW DISLOCATIONS; SIMULATION; STACKING FAULTS; THIN FILMS; VELOCITY

Citation Formats

Osetskiy, Yury N, Matsukawa, Yoshitaka, Stoller, Roger E, and Zinkle, Steven J. On the features of dislocation-obstacle interactions in thin films: direct comparison between in situ experiments and large scale computer modeling.. United States: N. p., 2006. Web. doi:10.1080/09500830600908988.
Osetskiy, Yury N, Matsukawa, Yoshitaka, Stoller, Roger E, & Zinkle, Steven J. On the features of dislocation-obstacle interactions in thin films: direct comparison between in situ experiments and large scale computer modeling.. United States. doi:10.1080/09500830600908988.
Osetskiy, Yury N, Matsukawa, Yoshitaka, Stoller, Roger E, and Zinkle, Steven J. Sun . "On the features of dislocation-obstacle interactions in thin films: direct comparison between in situ experiments and large scale computer modeling.". United States. doi:10.1080/09500830600908988.
@article{osti_958749,
title = {On the features of dislocation-obstacle interactions in thin films: direct comparison between in situ experiments and large scale computer modeling.},
author = {Osetskiy, Yury N and Matsukawa, Yoshitaka and Stoller, Roger E and Zinkle, Steven J},
abstractNote = {Large-scale atomistic modelling has demonstrated that the dynamic interactions of dislocations in thin films have a number of remarkable features. A particular example is the interaction between a screw dislocation and a stacking fault tetrahedron (SFT) in Cu, which can be directly compared with in situ observations of quenched or irradiated fcc metals. If the specimen is thin, the dislocation velocity is slow, and the temperature is high enough, a segment of the original SFT can be transported towards the surface via a double cross-slip mechanism and fast glide of an edge dislocation segment formed during the interaction. The mechanisms observed in the simulations provide an explanation for the results of in situ straining experiments and the differences between bulk and thin film experiments.},
doi = {10.1080/09500830600908988},
journal = {Philosophical Magazine Letters},
number = 8,
volume = 86,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
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