---
_id: '9684'
abstract:
- lang: eng
  text: The size dependence of the strength of nano- and micron-sized crystals is
    studied using a new simulation approach in which the dynamics of the density functions
    of dislocations are modeled. Since any quantity of dislocations can be represented
    by a density, this approach can handle large systems containing large quantities
    of dislocations, which may handicap discrete dislocation dynamics schemes due
    to the excessive computation time involved. For this reason, pillar sizes spanning
    a large range, from the sub-micron to micron regimes, can be simulated. The simulation
    results reveal the power-law relationship between strength and specimen size up
    to a certain size, beyond which the strength varies much more slowly with size.
    For specimens smaller than ~4000b, their strength is found to be controlled by
    the dislocation depletion condition, in which the total dislocation density remains
    almost constant throughout the loading process. In specimens larger than ~4000b,
    the initial dislocation distribution is of critical importance since the presence
    of dislocation entanglements is found to obstruct deformation in the neighboring
    regions within a distance of ~2000b. This length scale suggests that the effects
    of dense dislocation clusters are greater in intermediate-sized specimens (e.g.
    4000b and 8000b) than in larger specimens (e.g. 16 000b), according to the weakest-link
    concept.
article_number: '035001'
article_processing_charge: No
article_type: original
author:
- first_name: P S S
  full_name: Leung, P S S
  last_name: Leung
- first_name: H S
  full_name: Leung, H S
  last_name: Leung
- first_name: Bingqing
  full_name: Cheng, Bingqing
  id: cbe3cda4-d82c-11eb-8dc7-8ff94289fcc9
  last_name: Cheng
  orcid: 0000-0002-3584-9632
- first_name: A H W
  full_name: Ngan, A H W
  last_name: Ngan
citation:
  ama: Leung PSS, Leung HS, Cheng B, Ngan AHW. Size dependence of yield strength simulated
    by a dislocation-density function dynamics approach. <i>Modelling and Simulation
    in Materials Science and Engineering</i>. 2015;23(3). doi:<a href="https://doi.org/10.1088/0965-0393/23/3/035001">10.1088/0965-0393/23/3/035001</a>
  apa: Leung, P. S. S., Leung, H. S., Cheng, B., &#38; Ngan, A. H. W. (2015). Size
    dependence of yield strength simulated by a dislocation-density function dynamics
    approach. <i>Modelling and Simulation in Materials Science and Engineering</i>.
    IOP Publishing. <a href="https://doi.org/10.1088/0965-0393/23/3/035001">https://doi.org/10.1088/0965-0393/23/3/035001</a>
  chicago: Leung, P S S, H S Leung, Bingqing Cheng, and A H W Ngan. “Size Dependence
    of Yield Strength Simulated by a Dislocation-Density Function Dynamics Approach.”
    <i>Modelling and Simulation in Materials Science and Engineering</i>. IOP Publishing,
    2015. <a href="https://doi.org/10.1088/0965-0393/23/3/035001">https://doi.org/10.1088/0965-0393/23/3/035001</a>.
  ieee: P. S. S. Leung, H. S. Leung, B. Cheng, and A. H. W. Ngan, “Size dependence
    of yield strength simulated by a dislocation-density function dynamics approach,”
    <i>Modelling and Simulation in Materials Science and Engineering</i>, vol. 23,
    no. 3. IOP Publishing, 2015.
  ista: Leung PSS, Leung HS, Cheng B, Ngan AHW. 2015. Size dependence of yield strength
    simulated by a dislocation-density function dynamics approach. Modelling and Simulation
    in Materials Science and Engineering. 23(3), 035001.
  mla: Leung, P. S. S., et al. “Size Dependence of Yield Strength Simulated by a Dislocation-Density
    Function Dynamics Approach.” <i>Modelling and Simulation in Materials Science
    and Engineering</i>, vol. 23, no. 3, 035001, IOP Publishing, 2015, doi:<a href="https://doi.org/10.1088/0965-0393/23/3/035001">10.1088/0965-0393/23/3/035001</a>.
  short: P.S.S. Leung, H.S. Leung, B. Cheng, A.H.W. Ngan, Modelling and Simulation
    in Materials Science and Engineering 23 (2015).
date_created: 2021-07-19T09:11:12Z
date_published: 2015-04-01T00:00:00Z
date_updated: 2023-02-23T14:04:54Z
day: '01'
doi: 10.1088/0965-0393/23/3/035001
extern: '1'
intvolume: '        23'
issue: '3'
language:
- iso: eng
month: '04'
oa_version: None
publication: Modelling and Simulation in Materials Science and Engineering
publication_identifier:
  eissn:
  - 1361-651X
  issn:
  - 0965-0393
publication_status: published
publisher: IOP Publishing
quality_controlled: '1'
scopus_import: '1'
status: public
title: Size dependence of yield strength simulated by a dislocation-density function
  dynamics approach
type: journal_article
user_id: 6785fbc1-c503-11eb-8a32-93094b40e1cf
volume: 23
year: '2015'
...