Discrete dislocation dynamics simulations of surface induced size effects in plasticity

Chung Souk Han; Alexander Hartmaier; Huajian Gao; Yonggang Huang

doi:10.1016/j.msea.2005.09.075

Discrete dislocation dynamics simulations of surface induced size effects in plasticity

Chung Souk Han^*, Alexander Hartmaier, Huajian Gao, Yonggang Huang

^*Corresponding author for this work

Civil and Environmental Engineering

Research output: Contribution to journal › Article › peer-review

45 Scopus citations

Abstract

Experiments have shown that the presence of free surfaces may induce harder as well as softer deformation behaviors in a crystalline solid. In order to shed some light on these apparently contradictory findings, two-dimensional discrete dislocation dynamics simulations are performed to investigate the surface induced size effects. The simulations indicate that, depending on the surface density of dislocation sources, a free surface may act either as a dislocation sink or as a net dislocation source, and can accordingly exert opposite effects on dislocation density over a boundary layer thickness of up to 500nm into the bulk. This finding provides a possible explanation for the apparent contradictions in experimental observations.

Original language	English (US)
Pages (from-to)	225-233
Number of pages	9
Journal	Materials Science and Engineering: A
Volume	415
Issue number	1-2
DOIs	https://doi.org/10.1016/j.msea.2005.09.075
State	Published - Jan 15 2006

Funding

The authors gratefully acknowledge support from the NSF-NIRT Project: “Mechanism Based Modeling and Simulation in Nanomechanics”, through grant no. NSF CMS-0103257, under the direction of Dr. Ken Chong. Helpful discussions with William D. Nix of Stanford are also gratefully acknowledged.

Keywords

Discrete dislocation dynamics
Plasticity
Size effects
Surface effects

ASJC Scopus subject areas

General Materials Science
Condensed Matter Physics
Mechanics of Materials
Mechanical Engineering

Access to Document

10.1016/j.msea.2005.09.075

Cite this

@article{b3664ceda52d454cb121230e8dd70f1a,

title = "Discrete dislocation dynamics simulations of surface induced size effects in plasticity",

abstract = "Experiments have shown that the presence of free surfaces may induce harder as well as softer deformation behaviors in a crystalline solid. In order to shed some light on these apparently contradictory findings, two-dimensional discrete dislocation dynamics simulations are performed to investigate the surface induced size effects. The simulations indicate that, depending on the surface density of dislocation sources, a free surface may act either as a dislocation sink or as a net dislocation source, and can accordingly exert opposite effects on dislocation density over a boundary layer thickness of up to 500nm into the bulk. This finding provides a possible explanation for the apparent contradictions in experimental observations.",

keywords = "Discrete dislocation dynamics, Plasticity, Size effects, Surface effects",

author = "Han, {Chung Souk} and Alexander Hartmaier and Huajian Gao and Yonggang Huang",

note = "Funding Information: The authors gratefully acknowledge support from the NSF-NIRT Project: “Mechanism Based Modeling and Simulation in Nanomechanics”, through grant no. NSF CMS-0103257, under the direction of Dr. Ken Chong. Helpful discussions with William D. Nix of Stanford are also gratefully acknowledged. ",

year = "2006",

month = jan,

day = "15",

doi = "10.1016/j.msea.2005.09.075",

language = "English (US)",

volume = "415",

pages = "225--233",

journal = "Materials Science and Engineering: A",

issn = "0921-5093",

publisher = "Elsevier BV",

number = "1-2",

}

TY - JOUR

T1 - Discrete dislocation dynamics simulations of surface induced size effects in plasticity

AU - Han, Chung Souk

AU - Hartmaier, Alexander

AU - Gao, Huajian

AU - Huang, Yonggang

N1 - Funding Information: The authors gratefully acknowledge support from the NSF-NIRT Project: “Mechanism Based Modeling and Simulation in Nanomechanics”, through grant no. NSF CMS-0103257, under the direction of Dr. Ken Chong. Helpful discussions with William D. Nix of Stanford are also gratefully acknowledged.

PY - 2006/1/15

Y1 - 2006/1/15

N2 - Experiments have shown that the presence of free surfaces may induce harder as well as softer deformation behaviors in a crystalline solid. In order to shed some light on these apparently contradictory findings, two-dimensional discrete dislocation dynamics simulations are performed to investigate the surface induced size effects. The simulations indicate that, depending on the surface density of dislocation sources, a free surface may act either as a dislocation sink or as a net dislocation source, and can accordingly exert opposite effects on dislocation density over a boundary layer thickness of up to 500nm into the bulk. This finding provides a possible explanation for the apparent contradictions in experimental observations.

AB - Experiments have shown that the presence of free surfaces may induce harder as well as softer deformation behaviors in a crystalline solid. In order to shed some light on these apparently contradictory findings, two-dimensional discrete dislocation dynamics simulations are performed to investigate the surface induced size effects. The simulations indicate that, depending on the surface density of dislocation sources, a free surface may act either as a dislocation sink or as a net dislocation source, and can accordingly exert opposite effects on dislocation density over a boundary layer thickness of up to 500nm into the bulk. This finding provides a possible explanation for the apparent contradictions in experimental observations.

KW - Discrete dislocation dynamics

KW - Plasticity

KW - Size effects

KW - Surface effects

UR - http://www.scopus.com/inward/record.url?scp=29244474595&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=29244474595&partnerID=8YFLogxK

U2 - 10.1016/j.msea.2005.09.075

DO - 10.1016/j.msea.2005.09.075

M3 - Article

AN - SCOPUS:29244474595

SN - 0921-5093

VL - 415

SP - 225

EP - 233

JO - Materials Science and Engineering: A

JF - Materials Science and Engineering: A

IS - 1-2

ER -

Discrete dislocation dynamics simulations of surface induced size effects in plasticity

Abstract

Funding

Keywords

ASJC Scopus subject areas

Access to Document

Other files and links

Fingerprint

Cite this