Computer-Simulation Studies of Grain Boundary Systems and Molecular Solids.

Abstract

Structural, thermodynamic and mechanical properties of bicrystals have been studied using molecular dynamics and Monte Carlo simulation. A grain boundary melting transition in a two-dimensional system has been observed. Atomic diffusion along grain boundaries was investigated by following in detail the migration of a vacancy initially introduced into the bicrystal. The activation energy for vacancy migration in iron has been determined, and thermal activation of Frenkel pairs in the grain boundary core was observed. Structural phase transformation in stressed solids has been studied using an extended Monte Carlo method. Stress-strain relations obtained for iron showed the existence of bcc <-> fcc transition under tension or compression. Dynamical properties of a one-dimensional nonlinear lattice (the U4-lattice) have been analyzed in terms of kink propagation and damping and kink diffusion. Both perturbation theory and molecular dynamic calculations were carried out. (Author)

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Document Details

Document Type
Technical Report
Publication Date
Apr 20, 1983
Accession Number
ADA127545

Entities

People

  • Sidney Yip

Organizations

  • Massachusetts Institute of Technology

Tags

Communities of Interest

  • Human Systems

DTIC Thesaurus Topics

  • Computer Simulations
  • Crystal Lattices
  • Crystal Structure
  • Dynamics
  • Grain Boundaries
  • Materials
  • Materials Science
  • Mechanical Properties
  • Mechanics
  • Molecular Dynamics
  • Monte Carlo Method
  • Phase Transformations
  • Point Defects
  • Simulations
  • Stress Strain Relations
  • Stresses
  • Two Dimensional

Fields of Study

  • Materials science
  • Physics

Readers

  • Computational Fluid Dynamics (CFD)
  • Materials Science and Engineering.