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Title: Acceleration of the Particle Swarm Optimization for Peierls–Nabarro modeling of dislocations in conventional and high-entropy alloys

Abstract

Dislocations are among the most important defects in determining the mechanical properties of both conventional alloys and high-entropy alloys. The Peierls-Nabarro model supplies an efficient pathway to their geometries and mobility. The difficulty in solving the integro-differential Peierls-Nabarro equation is how to effectively avoid the local minima in the energy landscape of a dislocation core. Among the other methods to optimize the dislocation core structures, we choose the algorithm of Particle Swarm Optimization, an algorithm that simulates the social behaviors of organisms. By employing more particles (bigger swarm) and more iterative steps (allowing them to explore for longer time), the local minima can be effectively avoided. But this would require more computational cost. The advantage of this algorithm is that it is readily parallelized in modern high computing architecture. We demonstrate the performance of our parallelized algorithm scales linearly with the number of employed cores.

Authors:
 [1];  [2];  [1]
  1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  2. (Germany)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Oak Ridge Leadership Computing Facility (OLCF)
Sponsoring Org.:
USDOE
OSTI Identifier:
1361334
Alternate Identifier(s):
OSTI ID: 1396497
Grant/Contract Number:
AC05-00OR22725
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Computer Physics Communications
Additional Journal Information:
Journal Volume: 215; Journal Issue: C; Journal ID: ISSN 0010-4655
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE

Citation Formats

Pei, Zongrui, Max-Planck-Inst. fur Eisenforschung, Duseldorf, and Eisenbach, Markus. Acceleration of the Particle Swarm Optimization for Peierls–Nabarro modeling of dislocations in conventional and high-entropy alloys. United States: N. p., 2017. Web. doi:10.1016/j.cpc.2017.01.022.
Pei, Zongrui, Max-Planck-Inst. fur Eisenforschung, Duseldorf, & Eisenbach, Markus. Acceleration of the Particle Swarm Optimization for Peierls–Nabarro modeling of dislocations in conventional and high-entropy alloys. United States. doi:10.1016/j.cpc.2017.01.022.
Pei, Zongrui, Max-Planck-Inst. fur Eisenforschung, Duseldorf, and Eisenbach, Markus. Mon . "Acceleration of the Particle Swarm Optimization for Peierls–Nabarro modeling of dislocations in conventional and high-entropy alloys". United States. doi:10.1016/j.cpc.2017.01.022. https://www.osti.gov/servlets/purl/1361334.
@article{osti_1361334,
title = {Acceleration of the Particle Swarm Optimization for Peierls–Nabarro modeling of dislocations in conventional and high-entropy alloys},
author = {Pei, Zongrui and Max-Planck-Inst. fur Eisenforschung, Duseldorf and Eisenbach, Markus},
abstractNote = {Dislocations are among the most important defects in determining the mechanical properties of both conventional alloys and high-entropy alloys. The Peierls-Nabarro model supplies an efficient pathway to their geometries and mobility. The difficulty in solving the integro-differential Peierls-Nabarro equation is how to effectively avoid the local minima in the energy landscape of a dislocation core. Among the other methods to optimize the dislocation core structures, we choose the algorithm of Particle Swarm Optimization, an algorithm that simulates the social behaviors of organisms. By employing more particles (bigger swarm) and more iterative steps (allowing them to explore for longer time), the local minima can be effectively avoided. But this would require more computational cost. The advantage of this algorithm is that it is readily parallelized in modern high computing architecture. We demonstrate the performance of our parallelized algorithm scales linearly with the number of employed cores.},
doi = {10.1016/j.cpc.2017.01.022},
journal = {Computer Physics Communications},
number = C,
volume = 215,
place = {United States},
year = {Mon Feb 06 00:00:00 EST 2017},
month = {Mon Feb 06 00:00:00 EST 2017}
}

Journal Article:
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  • We show, using an atomistic model with a Stillinger-Weber potential (SWP), that in the absence of reconstruction, the basic assumption of the Peierls-Nabarro (PN) model that the dislocation core is spread within the glide plane is verified for silicon. The Peierls stress (PS) obtained from the two models are in quantitative agreement ({approx}0.3{mu}), when restoring forces obtained from first principles generalized stacking-fault energy surfaces are used in the PN model [B. Joos, Q. Ren, and M. S. Duesbery, Phys. Rev. B {bold 50}, 5890 (1994)]. The PS was found to be isotropic in the glide plane. Within the SWP modelmore » no evidence of dissociation in the shuffle dislocations is found but glide sets do separate into two partials.« less
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