Accession Number : AD0778963

Title :   Constitutive Equations for Elastic-Viscoplastic Strain Hardening Materials,

Corporate Author : TECHNION - ISRAEL INST OF TECH HAIFA DEPT OF MATERIALS ENGINEERING

Personal Author(s) : Bodner,S. R. ; Partom,Y.

Report Date : FEB 1974

Pagination or Media Count : 35

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)

Descriptors :   *Strain(Mechanics), *Elastic properties, *Plastic deformation, *Titanium, Strain hardening, Loads(Forces), Stresses, Israel

Subject Categories : Metallurgy and Metallography

Distribution Statement : APPROVED FOR PUBLIC RELEASE