Modeling microbending of thin films through discrete dislocation dynamics, continuum dislocation theory, and gradient plasticity

Katerina E Aifantis, Daniel Weygand, Christian Motz, Nikolaos Nikitas, Michael Zaiser

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

Constitutive models that describe crystal microplasticity in a continuum framework can be envisaged as average representations of the dynamics of dislocation systems. Thus, their performance needs to be assessed not only by their ability to correctly represent stress-strain characteristics on the specimen scale but also by their ability to correctly represent the evolution of internal stress and strain patterns. Three-dimensional discrete dislocation dynamics (3D DDD) simulations provide complete knowledge of this evolution, and averages over ensembles of statistically equivalent simulations can therefore be used to assess the performance of continuum models. In this study, we consider the bending of a free-standing thin film. From a continuum mechanics point of view, this is a one-dimensional (1D) problem as stress and strain fields vary only in one dimension. From a dislocation plasticity point of view, on the other hand, the spatial degrees of freedom associated with the bending and piling up of dislocations are essential. We compare the results of 3D DDD simulations with those obtained from a simple 1D gradient plasticity model and a more complex dislocation-based continuum model. Both models correctly reproduce the nontrivial strain patterns predicted by 3D DDD for the microbending problem.

Original languageEnglish (US)
Pages (from-to)612-618
Number of pages7
JournalJournal of Materials Research
Volume27
Issue number3
DOIs
StatePublished - Feb 14 2012
Externally publishedYes

Fingerprint

Dichlorodiphenyldichloroethane
plastic properties
Plasticity
continuums
Thin films
gradients
thin films
Continuum mechanics
Constitutive models
continuum mechanics
simulation
Piles
Residual stresses
stress distribution
residual stress
degrees of freedom
Crystals
crystals

Keywords

  • Dislocations
  • Grain boundaries
  • Microstructure

ASJC Scopus subject areas

  • Materials Science(all)
  • Mechanical Engineering
  • Mechanics of Materials
  • Condensed Matter Physics

Cite this

Modeling microbending of thin films through discrete dislocation dynamics, continuum dislocation theory, and gradient plasticity. / Aifantis, Katerina E; Weygand, Daniel; Motz, Christian; Nikitas, Nikolaos; Zaiser, Michael.

In: Journal of Materials Research, Vol. 27, No. 3, 14.02.2012, p. 612-618.

Research output: Contribution to journalArticle

Aifantis, Katerina E ; Weygand, Daniel ; Motz, Christian ; Nikitas, Nikolaos ; Zaiser, Michael. / Modeling microbending of thin films through discrete dislocation dynamics, continuum dislocation theory, and gradient plasticity. In: Journal of Materials Research. 2012 ; Vol. 27, No. 3. pp. 612-618.
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