The Effects of Stoichiometry on the Mechanical Properties of Icosahedral Boron Carbide Under Loading

Abstract

The effects of stoichiometry on the atomic structure and the related mechanical properties of boron carbide (B4C) have been studied using density functional theory and quantum molecular dynamics simulations. Computational cells of boron carbide containing up to 960 atoms and spanning compositions ranging from 6.7% to 26.7% carbon were used to determine the effects of stoichiometry on the atomic structure, elastic properties, and stress?strain response as a function of hydrostatic, uniaxial, and shear loading paths. It was found that different stoichiometries, as well as variable atomic arrangements within a fixed stoichiometry can have a significant impact on the yield stress of boron carbide when compressed uniaxially (by as much as 70% in some cases); the significantly reduced strength of boron carbide under shear loading is also demonstrated.

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Document Details

Document Type
Technical Report
Publication Date
Nov 19, 2012
Accession Number
ADA570863

Entities

People

  • Decarlos E. Taylor
  • James W. McCauley
  • T. W. Wright

Organizations

  • United States Army Research Laboratory

Tags

Communities of Interest

  • Energy and Power Technologies
  • Weapons Technologies

DTIC Thesaurus Topics

  • Atomic Structure
  • Atoms
  • Bulk Modulus
  • Computational Chemistry Methods
  • Computer Simulations
  • Crystal Lattices
  • Density Functional Theory
  • Dynamics
  • Elastic Properties
  • Mechanical Properties
  • Modulus Of Elasticity
  • Molecular Dynamics
  • Phase Diagrams
  • Raman Spectroscopy
  • Shear Modulus
  • Shear Strength
  • Simulations

Fields of Study

  • Materials science

Readers

  • Materials Science and Engineering.
  • Quantum Chemistry
  • Structural Health Monitoring of Composite Structures.

Technology Areas

  • Quantum Computing