• français
    • English
    français
  • Login
Help
View Item 
  •   Home
  • Laboratoire d'Etude des Microstructures et de Mécanique des Matériaux (LEM3)
  • View Item
  • Home
  • Laboratoire d'Etude des Microstructures et de Mécanique des Matériaux (LEM3)
  • View Item
JavaScript is disabled for your browser. Some features of this site may not work without it.

Uncoupled dissipation assumption to control elastic gaps in Gurtin-type strain gradient models

Communication sans acte
Author
ccJEBAHI, Mohamed
178323 Laboratoire d'Etude des Microstructures et de Mécanique des Matériaux [LEM3]
CAI, Lei
ccABED-MERAIM, Farid 

URI
http://hdl.handle.net/10985/20344
Date
2020

Abstract

Thanks to their capabilities in capturing size effects, strain gradient plasticity theories have received a strong scientific interest in the last two decades. However, despite the great scientific effort on these theories, several challenging issues related to them remain to be addressed. One of these issues is concerned with the description of the dissipative processes due to plastic strains and plastic strain gradients. In almost all existing strain gradient works, such processes are described using generalized effective plastic strain measures, which imply plastic strains and their gradients in a coupled manner. This kind of (coupled) measures makes the issue of proposing robust and flexible dissipation formulations and the control of important dissipative effects difficult. Using such measures, it is not easy to control, for example, the elastic gaps at initial yield or under non-proportional loading. However, in most cases, the coupling between dissipative processes is only used by assumption. Its consistency with the current understanding of small scale plasticity is not confirmed in the literature. In spirit of multi-criterion approaches available in the literature, the present work proposes a flexible uncoupled dissipation assumption to describe dissipative processes. These processes are assumed to be derived from a pseudo-potential that is a sum of two independent functions of plastic strains and plastic strain gradients. Using this assumption, a new Gurtin-type strain gradient crystal plasticity (SGCP) model is developed and applied to simulate various two-dimensional plane-strain tests under proportional and non-proportional loading conditions. Results associated with these tests show the great flexibility of the proposed model in controlling some major dissipative effects, such as elastic gaps. A simple way to remove these gaps under certain non-proportional loading conditions is provided. Application of the proposed uncoupling assumption to simulate the mechanical response of a sheared strip has led to accurate prediction of the plastic strain distributions, which compare very favorably with those predicted using discrete dislocation mechanics.

Files in this item

Name:
LEM3_ICPDF_2020_JEBAHI.pdf
Size:
394.9Kb
Format:
PDF
View/Open

Collections

  • Laboratoire d'Etude des Microstructures et de Mécanique des Matériaux (LEM3)

Related items

Showing items related by title, author, creator and subject.

  • Strain gradient crystal plasticity model based on generalized non-quadratic defect energy and uncoupled dissipation 
    Article dans une revue avec comité de lecture
    ccJEBAHI, Mohamed; CAI, Lei; ccABED-MERAIM, Farid  (Elsevier, 2020)
    The present paper proposes a flexible Gurtin-type strain gradient crystal plasticity (SGCP) model based on generalized non-quadratic defect energy and uncoupled constitutive assumption for dissipative processes. A power-law ...
  • On the application of strain gradient crystal plasticity to study strain localization phenomena in single crystals 
    Communication sans acte
    CAI, Lei; ccJEBAHI, Mohamed; ccABED-MERAIM, Farid  (2021)
    Strain localization is an important plastic instability process occurring prior to fracture. It is usually observed in the form of narrow bands of intense plastic shear strain in deformed bodies undergoing severe inhomogeneous ...
  • Strain Localization Modes within Single Crystals Using Finite Deformation Strain Gradient Crystal Plasticity 
    Article dans une revue avec comité de lecture
    CAI, Lei; ccJEBAHI, Mohamed; ccABED-MERAIM, Farid  (MDPI AG, 2021)
    The present paper aims at providing a comprehensive investigation of the abilities and limitations of strain gradient crystal plasticity (SGCP) theories in capturing different kinds of localization modes in single crystals. ...
  • On the application of strain gradient crystal plasticity to study strain localization phenomena in single crystals 
    Communication sans acte
    CAI, Lei; ccJEBAHI, Mohamed; ccABED-MERAIM, Farid  (2021)
    Strain localization is an important plastic instability process occurring prior to fracture. It is usually observed in the form of narrow bands of intense plastic shear strain in deformed bodies undergoing severe inhomogeneous ...
  • On the non-quadratic defect energy in strain gradient crystal plasticity 
    Communication avec acte
    CAI, Lei; ccJEBAHI, Mohamed; ccABED-MERAIM, Farid  (2019)
    Strain gradient crystal plasticity (SGCP) represents a very promising way to account for size effects in miniaturized components, thanks to the intrinsic length scale(s) embedded. Most of the existing SGCP models are based ...

Browse

All SAMCommunities & CollectionsAuthorsIssue DateCenter / InstitutionThis CollectionAuthorsIssue DateCenter / Institution

Newsletter

Latest newsletterPrevious newsletters

Statistics

Most Popular ItemsStatistics by CountryMost Popular Authors

ÉCOLE NATIONALE SUPERIEURE D'ARTS ET METIERS

  • Contact
  • Mentions légales

ÉCOLE NATIONALE SUPERIEURE D'ARTS ET METIERS

  • Contact
  • Mentions légales