Constitutive Equations for Elastic-Viscoplastic Strain Hardening Materials,

Abstract

A set of constitutive equations has been formulated to represent elastic-viscoplastic strain hardening material behavior for large deformations and arbitrary loading histories. An essential feature of the formulation is that the total deformation rate is considered to be separable into elastic and inelastic components which are functions of state variables at all stages of loading and unloading. The theory, therefore, is independent of a yield criterion or loading and unloading conditions. The deformation rate components are determinable from the current state which permits an incremental formulation of problems. Strain hardening is considered in the equations by introducing plastic work as the representative state variable. The problem of uniaxial straining has been examined for a number of histories that included straining at various rates, rapid changes of strain rate, unloading and reloading, and stress relaxation. The calculations were based on material constants chosen to represent commercially pure titanium. The results are in good agreement with corresponding experiments on titanium specimens. (Author)

Document Details

Document Type
Technical Report
Publication Date
Feb 01, 1974
Accession Number
AD0778963

Entities

People

  • S. R. Bodner
  • Y. Partom

Organizations

  • Technion – Israel Institute of Technology

Tags

DTIC Thesaurus Topics

  • Agreements
  • Constitutive Equations
  • Equations
  • Hardening
  • Materials
  • Strain Hardening
  • Strain Rate
  • Titanium
  • Unloading

Readers

  • Mechanical Engineering/Mechanics of Materials.
  • Operations Research