On the Definition of State Variables for an Internal State Variable Constitutive Model Describing Metal Deformation

Paul S. Follansbee

Boyer School of Natural Sciences, Mathematics, and Computing, Saint Vincent College, Latrobe, USA.

DOI: 10.4236/msa.2014.58062                

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.

Keywords

Consitutive Modeling, Internal State Variable, Metal Deformation, Ideal Gas Law, Path Dependence

Conflicts of Interest

The authors declare no conflicts of interest.

References

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