Accession Number : AD0779855

Title :   Restrictions on Constitutive Equations of Finitely Deformed Elastic-Plastic Materials.

Descriptive Note : Technical rept.,

Corporate Author : CALIFORNIA UNIV BERKELEY DEPT OF MECHANICAL ENGINEERING

Personal Author(s) : Naghdi,P. M. ; Trapp,J. A.

Report Date : APR 1974

Pagination or Media Count : 38

Abstract : The paper is concerned with restrictions on the constitutive equations of elastic-plastic materials in the presence of large deformation. The development is confined to the purely mechanical theory in which the response of the medium is characterized by nonlinear constitutive equations of rate-type. Starting with a physically plausible assumption concerning non-negative work in a closed cycle of deformation, tha authors derive two local inequalities which hold in all motions and which place restrictions on the general constitutive equations of elastic-plastic materials. An implication of one of the inequalities is then used to express the constitutive equation for the plastic strain rate in terms of the yield (or loading) function, as well as the stress response and a measure of work hardening. (Author)

Descriptors :   *Deformation, *Elastic properties, *Plastic properties, Numerical analysis, Strain rate

Subject Categories : Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE