A Predictive Multiscale Model of Wear

Abstract

This report describes the development of an ab initio version of density functional theory + U (DFT+U) theory that then permitted high quality quantum mechanics simulations of the tensile and shear properties of chromium and iron oxides. A multiscale model that had been devised earlier by the PI for describing tensile load response was extended to study shear deformation across scales. Analysis of atomic scale deformations provided insight into the mechanical properties (e.g., tensile and shear strengths and moduli)calculated. The oxides were shown to yield more easily via shearing than via tensile displacements, which can be understood by the reduced loss of metal-oxygen bonds during shear. The relative ease of shearing has implications for the oxides forming in gun tubes, namely that despite their brittle nature, the shear forces exerted by the propellant gases and projectile are largely responsible for wear in gun tubes.

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Document Details

Document Type
Technical Report
Publication Date
Mar 09, 2011
Accession Number
ADA544762

Entities

People

  • Emily A. Carter

Organizations

  • Princeton University

Tags

Communities of Interest

  • Advanced Electronics
  • Air Platforms
  • Energy and Power Technologies
  • Weapons Technologies

DTIC Thesaurus Topics

  • Chemistry
  • Computational Chemistry
  • Density Functional Theory
  • Dynamical Mean Field Theory
  • Engineering
  • Iron Oxides
  • Materials
  • Mechanical Properties
  • Mechanics
  • Metal Oxides
  • Multiscale Models
  • Physical Chemistry
  • Shear Strength
  • Solid State Physics
  • Tensile Properties
  • Tensile Strength
  • Transition Metals

Readers

  • Computational Fluid Dynamics (CFD)
  • Mechanical Engineering/Mechanics of Materials.
  • Quantum Chemistry

Technology Areas

  • Quantum Computing