Accession Number : AD0711401

Title :   THERMODYNAMICS OF MATERIALS WITH MEMORY.

Descriptive Note : Doctoral thesis,

Corporate Author : UTAH UNIV SALT LAKE CITY COLL OF ENGINEERING

Personal Author(s) : Hufferd,William L.

Report Date : MAY 1970

Pagination or Media Count : 211

Abstract : A continuum thermodynamic theory of nonlinear thermomechanical materials with memory is developed and its application to the observed behavior of real materials discussed. Following a review and summary of the basic concepts of modern continuum mechanics an in-depth discussion and appraisal of the axiomatic foundations of thermomechanical constitutive theory is presented. An extended principle of equipresence is proposed which appears to be necessary for the rigorous axiomatic development of thermomechanical constitutive theories. A new physical principle of fading memory is next introduced which extends previous principles of fading memory to include finite memory and permanent memory. Coupling between memory effects under different loading situations is allowed. Coleman's continuum thermodynamic theory is also extended to admit materials and processes capable of instantaneous dissipation. With these extensions, the constitutive theory developed herein admits classes of materials and processes which are more closely related to the observed physical behavior of real materials under a variety of loading environments. In particular, the constitutive theory is directly applicable to viscoelastic solids, inelastic deformations such as plasticity and viscoplasticity, and reduces to previous special theories of idealized materials under appropriate simplifying assumptions. (Author)

Descriptors :   (*CONTINUUM MECHANICS, *THERMODYNAMICS), (*VISCOELASTICITY, MATHEMATICAL MODELS), (*PLASTIC PROPERTIES, MATHEMATICAL MODELS), TENSOR ANALYSIS, DEFORMATION, STRESSES, THESES

Subject Categories : Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE