Modeling of thermally activated dislocation glide and plastic flow through local obstacles

M. Hiratani, H. M. Zbib, M. A. Khaleel

Research output: Contribution to journalArticle

43 Citations (Scopus)

Abstract

A unified phenomenological model is developed to study the dislocation glide through weak obstacles during the first stage of plastic deformation in metals. This model takes into account both the dynamical responses of dislocations during the flight process and thermal activations while dislocations are bound by obstacle arrays. The average thermal activation rate is estimated using an analytical model based on the generalized Friedel relations. Then, the average flight velocity after an activation event is obtained numerically by discrete dislocation dynamics (DD). To simulate the dynamical dislocation behavior, the inertia term is implemented into the equation of dislocation motion within the DD code. The results from the DD simulations, coupled with the analytical model, determine the total dislocation velocity as a function of the stress and temperatures. By choosing parameters typical of the face centered cubic metals, the model reproduces both obstacle control and drag control motion in low and high velocity regimes, respectively. As expected by other string models, dislocation overshoots of obstacles caused by the dislocation inertia at the collisions are enhanced as temperature goes down.

Original languageEnglish
Pages (from-to)1271-1296
Number of pages26
JournalInternational Journal of Plasticity
Volume19
Issue number9
DOIs
Publication statusPublished - 1 Sep 2003
Externally publishedYes

Fingerprint

Plastic flow
Chemical activation
Analytical models
Metals
Motion control
Drag
Plastic deformation
Temperature
Computer simulation
Hot Temperature

Keywords

  • A. Creep
  • A. Dislocations
  • A. Strengthening mechanisms
  • B. Metallic materials
  • C. Probability and statistics

ASJC Scopus subject areas

  • Mechanical Engineering

Cite this

Modeling of thermally activated dislocation glide and plastic flow through local obstacles. / Hiratani, M.; Zbib, H. M.; Khaleel, M. A.

In: International Journal of Plasticity, Vol. 19, No. 9, 01.09.2003, p. 1271-1296.

Research output: Contribution to journalArticle

Hiratani, M. ; Zbib, H. M. ; Khaleel, M. A. / Modeling of thermally activated dislocation glide and plastic flow through local obstacles. In: International Journal of Plasticity. 2003 ; Vol. 19, No. 9. pp. 1271-1296.
@article{cee1a902dc6d497bbdc978fb3e41b820,
title = "Modeling of thermally activated dislocation glide and plastic flow through local obstacles",
abstract = "A unified phenomenological model is developed to study the dislocation glide through weak obstacles during the first stage of plastic deformation in metals. This model takes into account both the dynamical responses of dislocations during the flight process and thermal activations while dislocations are bound by obstacle arrays. The average thermal activation rate is estimated using an analytical model based on the generalized Friedel relations. Then, the average flight velocity after an activation event is obtained numerically by discrete dislocation dynamics (DD). To simulate the dynamical dislocation behavior, the inertia term is implemented into the equation of dislocation motion within the DD code. The results from the DD simulations, coupled with the analytical model, determine the total dislocation velocity as a function of the stress and temperatures. By choosing parameters typical of the face centered cubic metals, the model reproduces both obstacle control and drag control motion in low and high velocity regimes, respectively. As expected by other string models, dislocation overshoots of obstacles caused by the dislocation inertia at the collisions are enhanced as temperature goes down.",
keywords = "A. Creep, A. Dislocations, A. Strengthening mechanisms, B. Metallic materials, C. Probability and statistics",
author = "M. Hiratani and Zbib, {H. M.} and Khaleel, {M. A.}",
year = "2003",
month = "9",
day = "1",
doi = "10.1016/S0749-6419(02)00016-5",
language = "English",
volume = "19",
pages = "1271--1296",
journal = "International Journal of Plasticity",
issn = "0749-6419",
publisher = "Elsevier Limited",
number = "9",

}

TY - JOUR

T1 - Modeling of thermally activated dislocation glide and plastic flow through local obstacles

AU - Hiratani, M.

AU - Zbib, H. M.

AU - Khaleel, M. A.

PY - 2003/9/1

Y1 - 2003/9/1

N2 - A unified phenomenological model is developed to study the dislocation glide through weak obstacles during the first stage of plastic deformation in metals. This model takes into account both the dynamical responses of dislocations during the flight process and thermal activations while dislocations are bound by obstacle arrays. The average thermal activation rate is estimated using an analytical model based on the generalized Friedel relations. Then, the average flight velocity after an activation event is obtained numerically by discrete dislocation dynamics (DD). To simulate the dynamical dislocation behavior, the inertia term is implemented into the equation of dislocation motion within the DD code. The results from the DD simulations, coupled with the analytical model, determine the total dislocation velocity as a function of the stress and temperatures. By choosing parameters typical of the face centered cubic metals, the model reproduces both obstacle control and drag control motion in low and high velocity regimes, respectively. As expected by other string models, dislocation overshoots of obstacles caused by the dislocation inertia at the collisions are enhanced as temperature goes down.

AB - A unified phenomenological model is developed to study the dislocation glide through weak obstacles during the first stage of plastic deformation in metals. This model takes into account both the dynamical responses of dislocations during the flight process and thermal activations while dislocations are bound by obstacle arrays. The average thermal activation rate is estimated using an analytical model based on the generalized Friedel relations. Then, the average flight velocity after an activation event is obtained numerically by discrete dislocation dynamics (DD). To simulate the dynamical dislocation behavior, the inertia term is implemented into the equation of dislocation motion within the DD code. The results from the DD simulations, coupled with the analytical model, determine the total dislocation velocity as a function of the stress and temperatures. By choosing parameters typical of the face centered cubic metals, the model reproduces both obstacle control and drag control motion in low and high velocity regimes, respectively. As expected by other string models, dislocation overshoots of obstacles caused by the dislocation inertia at the collisions are enhanced as temperature goes down.

KW - A. Creep

KW - A. Dislocations

KW - A. Strengthening mechanisms

KW - B. Metallic materials

KW - C. Probability and statistics

UR - http://www.scopus.com/inward/record.url?scp=0037412133&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0037412133&partnerID=8YFLogxK

U2 - 10.1016/S0749-6419(02)00016-5

DO - 10.1016/S0749-6419(02)00016-5

M3 - Article

AN - SCOPUS:0037412133

VL - 19

SP - 1271

EP - 1296

JO - International Journal of Plasticity

JF - International Journal of Plasticity

SN - 0749-6419

IS - 9

ER -