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
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
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U2 - 10.1016/j.msea.2005.09.075
DO - 10.1016/j.msea.2005.09.075
M3 - Article
AN - SCOPUS:29244474595
VL - 415
SP - 225
EP - 233
JO - Materials Science & Engineering A: Structural Materials: Properties, Microstructure and Processing
JF - Materials Science & Engineering A: Structural Materials: Properties, Microstructure and Processing
SN - 0921-5093
IS - 1-2
ER -