TITLE:
On the Definition of State Variables for an Internal State Variable Constitutive Model Describing Metal Deformation
AUTHORS:
Paul S. Follansbee
KEYWORDS:
Consitutive Modeling, Internal State Variable, Metal Deformation, Ideal Gas Law, Path Dependence
JOURNAL NAME:
Materials Sciences and Applications,
Vol.5 No.8,
June
30,
2014
ABSTRACT:
The quest for an internal state variable constitutive model describing
metal deformation is reviewed. First, analogy is drawn between a deformation
model and the Ideal Gas Law. The use of strain as a variable in deformation
models is discussed, and whether strain serves as an internal state variable is
considered. A simple experiment that demonstrated path dependence in copper is
described. The importance of defining appropriate internal state variables for
a constitutive law relates to the ability to accurately model temperature and
strain-rate dependencies in deformation simulations.