Two-Temperature Continuum Model for Metal Plasticity

  • Debasish Roy Computational Mechanics Lab., Department of Civil Engineering, Indian Institute of Science, Bangalore 560 012, India
Keywords: Metal Viscoplasticity, Non-Equilibrium Thermodynamics, Two-Temperature Framework, Dislocation Density

Abstract

A physically based continuum plasticity model for metals from the consideration of non-equilibrium thermodynamics is presented. The modeling is accomplished in a two-temperature framework that appears naturally by considering the
thermodynamic system to be composed of two weakly interacting subsystems, namely the kinetic vibrational and configurational subsystems. While the atomic vibrations of plastically deforming metals form the kinetic vibrational subsystem, much slower degrees of freedom in terms of the motion of defects constitute the configurational subsystem. Both subsystems assume their own temperatures and fall out of equilibrium from each other because of the externally imposed driving. Dislocation density characterising the configurational subsystem is considered to be the state variable for the present development. The continuum model accommodates finite deformation and describes plastic deformation in a yield-free framework via a microforce balance along with the conventional macroforce balance.

Published
2016-07-21