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Title: Dislocation Glasses: Aging during Relaxation and Coarsening

Abstract

The dynamics of dislocations is reported to exhibit a range of glassy properties. We study numerically various versions of 2D edge dislocation systems, in the absence of externally applied stress. Two types of glassy behavior are identified (i) dislocations gliding along randomly placed, but fixed, axes exhibit relaxation to their spatially disordered stable state; (ii) if both climb and annihilation are allowed, irregular cellular structures can form on a growing length scale before all dislocations annihilate. In all cases both the correlation function and the diffusion coefficient are found to exhibit aging. Relaxation in case (i) is a slow power law, furthermore, in the transient process (ii) the dynamical exponent z{approx_equal}6, i.e., the cellular structure coarsens relatively slowly.

Authors:
; ; ;  [1];  [2];  [3]
  1. Department of Materials Physics, Eoetvoes University, Pazmany setany 1/A, 1117 Budapest (Hungary)
  2. (Hungary)
  3. (United States)
Publication Date:
OSTI Identifier:
20955473
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 7; Other Information: DOI: 10.1103/PhysRevLett.98.075701; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; AGING; ANNIHILATION; CORRELATION FUNCTIONS; EDGE DISLOCATIONS; GLASS; RELAXATION

Citation Formats

Bako, B., Groma, I., Gyoergyi, G., Zimanyi, G. T., Institute for Theoretical Physics, HAS Research Groups, Eoetvoes University, Pazmany setany 1/A, 1117 Budapest, and Department of Physics, University of California, Davis. Dislocation Glasses: Aging during Relaxation and Coarsening. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.075701.
Bako, B., Groma, I., Gyoergyi, G., Zimanyi, G. T., Institute for Theoretical Physics, HAS Research Groups, Eoetvoes University, Pazmany setany 1/A, 1117 Budapest, & Department of Physics, University of California, Davis. Dislocation Glasses: Aging during Relaxation and Coarsening. United States. doi:10.1103/PHYSREVLETT.98.075701.
Bako, B., Groma, I., Gyoergyi, G., Zimanyi, G. T., Institute for Theoretical Physics, HAS Research Groups, Eoetvoes University, Pazmany setany 1/A, 1117 Budapest, and Department of Physics, University of California, Davis. Fri . "Dislocation Glasses: Aging during Relaxation and Coarsening". United States. doi:10.1103/PHYSREVLETT.98.075701.
@article{osti_20955473,
title = {Dislocation Glasses: Aging during Relaxation and Coarsening},
author = {Bako, B. and Groma, I. and Gyoergyi, G. and Zimanyi, G. T. and Institute for Theoretical Physics, HAS Research Groups, Eoetvoes University, Pazmany setany 1/A, 1117 Budapest and Department of Physics, University of California, Davis},
abstractNote = {The dynamics of dislocations is reported to exhibit a range of glassy properties. We study numerically various versions of 2D edge dislocation systems, in the absence of externally applied stress. Two types of glassy behavior are identified (i) dislocations gliding along randomly placed, but fixed, axes exhibit relaxation to their spatially disordered stable state; (ii) if both climb and annihilation are allowed, irregular cellular structures can form on a growing length scale before all dislocations annihilate. In all cases both the correlation function and the diffusion coefficient are found to exhibit aging. Relaxation in case (i) is a slow power law, furthermore, in the transient process (ii) the dynamical exponent z{approx_equal}6, i.e., the cellular structure coarsens relatively slowly.},
doi = {10.1103/PHYSREVLETT.98.075701},
journal = {Physical Review Letters},
number = 7,
volume = 98,
place = {United States},
year = {Fri Feb 16 00:00:00 EST 2007},
month = {Fri Feb 16 00:00:00 EST 2007}
}
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