Publication detail

Uniqueness and stability of activated dislocation shapes in crystals

GRÖGER, R. ŠREMR, J. VYDROVÁ, J.

Original Title

Uniqueness and stability of activated dislocation shapes in crystals

Type

journal article in Web of Science

Language

English

Original Abstract

Simplified models of thermally activated dislocation glide constitute an important link between atomic-level studies of isolated dislocations and macroscopic thermodynamic properties of materials. These models rest upon the activation enthalpy, which is the energy to transform an initially straight dislocation into its activated state at finite applied stresses. Minimizing this activation enthalpy leads to a boundary value problem for the shape of the dislocation line. Besides two constant solutions corresponding to a straight dislocation in its stable and unstable states at the applied stress, there exist an infinite number of non-constant solutions. We investigate the characters of these solutions for dislocations anchored at their ends. Using the second variation of the activation enthalpy, we derive a set of conditions that define a unique activated state of the dislocation. The corresponding analysis demonstrates that the shape of the dislocation in this activated state must change with the applied stress to maintain the state of minimum activation enthalpy.

Keywords

dislocations;slip;activation enthalpy;boundary value problem;uniqueness;stability

Authors

GRÖGER, R.; ŠREMR, J.; VYDROVÁ, J.

Released

2. 2. 2021

Publisher

IOP Publishing Ltd

Location

UK

ISBN

0965-0393

Periodical

MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING

Year of study

2021

Number

29

State

United Kingdom of Great Britain and Northern Ireland

Pages from

1

Pages to

13

Pages count

13

URL

https://iopscience.iop.org/article/10.1088/1361-651X/abd041

BibTex

@article{BUT169198,
  author="Roman {Gröger} and Jiří {Šremr} and Jana {Vydrová}",
  title="Uniqueness and stability of activated dislocation shapes in crystals",
  journal="MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING",
  year="2021",
  volume="2021",
  number="29",
  pages="1--13",
  doi="10.1088/1361-651X/abd041",
  issn="0965-0393",
  url="https://iopscience.iop.org/article/10.1088/1361-651X/abd041"
}