A New, General Theory of Plasticity for Structural Metal Alloys

Abstract

A new, general theory of plasticity for structural metal alloys of steel, aluminum, and copper is presented. Based on experiment, general constitutive equations are provided in the two-dimensional domain for any arbitrary loading path, whether proportional or non-proportional. Two regions of large deformation have been found, an intermediate elastic-plastic region and a totally plastic region, the former bounded by an inner and outer yield surface. The functional relation between the generalized stress and strain is parabolic, with detailed constitutive relations given for each region of deformation. A new phenomenon of 'eruptive' plastic deformation has been found when impact velocities are sufficiently high for the strain to reach the outer yield surface bounding the regions of plasticity. At this critical velocity the maximum strain increases from three to eight times, depending on the alloy, over that immediately below the critical value.

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Document Details

Document Type
Technical Report
Publication Date
Jul 01, 1975
Accession Number
ADA014192

Entities

People

  • James F. Bell

Organizations

  • Johns Hopkins University

Tags

Communities of Interest

  • Weapons Technologies

DTIC Thesaurus Topics

  • Aluminum Alloys
  • Applied Mechanics
  • Constitutive Equations
  • Crystal Structure
  • Crystals
  • Elastic Properties
  • Engineering
  • Jet Propulsion
  • Materials
  • Materials Engineering
  • Materials Science
  • Mechanical Engineering
  • Mechanics
  • Military Research
  • Plastic Properties
  • Polycrystals
  • Wave Propagation

Readers

  • Fluid Mechanics and Fluid Dynamics.
  • Mathematical Modeling and Probability Theory.
  • Mechanical Engineering/Mechanics of Materials.