Dislocation Dynamics Simulations of Junctions in Hexagonal Close-Packed Crystals

Abstract

The formation and strength of dislocations in the hexagonal closed packed material beryllium are studied through dislocation junctions and the critical stress required to break them. Dislocation dynamics calculations (using the code ParaDiS) of junction maps are compared to an analytical line tension approximation in order to validate our model. Results show that the two models agree very well. Also the critical shear stress necessary to break 30o - 30o and 30o - 90o dislocation junctions is computed numerically. Yield surfaces are mapped out for these junctions to describe their stability regions as function of resolved shear stresses on the glide planes. The example of two non-coplanar binary dislocation junctions with slip planes [2-1-10] (01-10) and [-12-10] (0001) corresponding to a prismatic and basal slip respectively is chosen to verify and validate our implementation.

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Document Details

Document Type
Technical Report
Publication Date
Dec 13, 2011
Accession Number
ADA556651

Entities

People

  • Athanasios Arsenlis
  • Chi-chin Wu
  • Peter W Chung
  • Sylvie Aubry

Organizations

  • United States Army Research Laboratory

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Coordinate Systems
  • Crystal Structure
  • Crystals
  • Dislocations
  • Dynamics
  • Governments
  • Materials
  • Materials Science
  • Military Research
  • National Security
  • Poisson Ratio
  • Shear Modulus
  • Shear Stresses
  • Simulations
  • Stresses
  • United States
  • United States Government

Fields of Study

  • Physics

Readers

  • Computational Modeling and Simulation
  • Materials Science and Engineering.