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.
Cite this paper
Follansbee, P. (2014) On the Definition of State Variables for an Internal State Variable Constitutive Model Describing Metal Deformation. Materials Sciences and Applications
, 603-609. doi: 10.4236/msa.2014.58062
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