Crystal Thermoelasticity at Extreme Loading Rates and Pressures: Analysis of Higher-Order Energy Potentials

Abstract

Several finite elastic strain measures are evaluated for use in constitutive models of crystalline elasticity and elasto-plasticity. These include the Green material strain tensor, the Eulerian material strain tensor, and the logarithmic material strain tensor, all of which are referred to locally relaxed coordinates invariant under spatial rotations. New applications of logarithmic strain-based theory towards shock compression of aluminum, copper, and magnesium single crystals and polycrystals are presented. Solutions to the planar shock problem from previous work are summarized and compared with the present results. Consideration of these new results in conjunction with previous analysis for a number of different metals, ceramics, and minerals suggests that Eulerian strain-based theory is most accurate for modeling the dynamic high-pressure response of ductile metallic crystals wherein ratios of elastic shear to bulk moduli tend to be relatively small, while logarithmic strainbased theory is recommended for modeling shocks in ceramics and minerals with larger ratios of effective elastic shear to bulk modulus.

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Document Details

Document Type
Technical Report
Publication Date
Jul 01, 2015
Accession Number
ADA618581

Entities

People

  • John D. Clayton

Organizations

  • United States Army Research Laboratory

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Aluminum
  • Bulk Modulus
  • Compression
  • Continuum Mechanics
  • Crystals
  • Elastic Properties
  • Elements
  • Experimental Data
  • High Pressure
  • Materials
  • Mechanics
  • Metals
  • Molecular Dynamics
  • Physical Properties
  • Polycrystals
  • Single Crystals
  • Thermoelasticity

Readers

  • Fluid Dynamics.
  • Materials Science and Engineering.
  • Mechanical Engineering/Mechanics of Materials.