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Title: Scaling laws and deformation mechanisms of nanoporous copper under adiabatic uniaxial strain compression

Abstract

A series of large-scale molecular dynamics simulations were conducted to investigate the scaling laws and the related atomistic deformation mechanisms of Cu monocrystal samples containing randomly placed nanovoids under adiabatic uniaxial strain compression. At onset of yielding, plastic deformation is accommodated by dislocations emitted from void surfaces as shear loops. The collapse of voids are observed by continuous emissions of dislocations from void surfaces and their interactions with further plastic deformation. The simulation results also suggest that the effect modulus, the yield stress and the energy aborption density of samples under uniaxial strain are linearly proportional to the relative density ρ. Moreover, the yield stress, the average flow stress and the energy aborption density of samples with the same relative density show a strong dependence on the void diameter d, expressed by exponential relations with decay coefficients much higher than -1/2. The corresponding atomistic mechanisms for scaling laws of the relative density and the void diameter were also presented. The present results should provide insights for understanding deformation mechanisms of nanoporous metals under extreme conditions.

Authors:
;  [1]
  1. State Key Laboratory of Nonlinear Mechanics, Institute of Mechanics, Chinese Academy of Science, No.15, North 4th Ring, West Road, Beijing 100190 (China)
Publication Date:
OSTI Identifier:
22420195
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Advances; Journal Volume: 4; Journal Issue: 12; Other Information: (c) 2014 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; COMPRESSION; COPPER; DEFORMATION; DENSITY; DISLOCATIONS; EMISSION; FLOW STRESS; INTERACTIONS; MOLECULAR DYNAMICS METHOD; MONOCRYSTALS; NANOSTRUCTURES; PLASTICITY; SCALING LAWS; SIMULATION; STRAINS; VOIDS

Citation Formats

Yuan, Fuping, E-mail: fpyuan@lnm.imech.ac.cn, and Wu, Xiaolei, E-mail: xlwu@imech.ac.cn. Scaling laws and deformation mechanisms of nanoporous copper under adiabatic uniaxial strain compression. United States: N. p., 2014. Web. doi:10.1063/1.4903549.
Yuan, Fuping, E-mail: fpyuan@lnm.imech.ac.cn, & Wu, Xiaolei, E-mail: xlwu@imech.ac.cn. Scaling laws and deformation mechanisms of nanoporous copper under adiabatic uniaxial strain compression. United States. doi:10.1063/1.4903549.
Yuan, Fuping, E-mail: fpyuan@lnm.imech.ac.cn, and Wu, Xiaolei, E-mail: xlwu@imech.ac.cn. 2014. "Scaling laws and deformation mechanisms of nanoporous copper under adiabatic uniaxial strain compression". United States. doi:10.1063/1.4903549.
@article{osti_22420195,
title = {Scaling laws and deformation mechanisms of nanoporous copper under adiabatic uniaxial strain compression},
author = {Yuan, Fuping, E-mail: fpyuan@lnm.imech.ac.cn and Wu, Xiaolei, E-mail: xlwu@imech.ac.cn},
abstractNote = {A series of large-scale molecular dynamics simulations were conducted to investigate the scaling laws and the related atomistic deformation mechanisms of Cu monocrystal samples containing randomly placed nanovoids under adiabatic uniaxial strain compression. At onset of yielding, plastic deformation is accommodated by dislocations emitted from void surfaces as shear loops. The collapse of voids are observed by continuous emissions of dislocations from void surfaces and their interactions with further plastic deformation. The simulation results also suggest that the effect modulus, the yield stress and the energy aborption density of samples under uniaxial strain are linearly proportional to the relative density ρ. Moreover, the yield stress, the average flow stress and the energy aborption density of samples with the same relative density show a strong dependence on the void diameter d, expressed by exponential relations with decay coefficients much higher than -1/2. The corresponding atomistic mechanisms for scaling laws of the relative density and the void diameter were also presented. The present results should provide insights for understanding deformation mechanisms of nanoporous metals under extreme conditions.},
doi = {10.1063/1.4903549},
journal = {AIP Advances},
number = 12,
volume = 4,
place = {United States},
year = 2014,
month =
}
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