Unified Micromechanics of Finite Deformations

In this chapter finite (large) deformation micromechanics is discussed. Formulation is more complicated than small deformation theory; therefore, it is easier to explain with an example. Micromechanical modeling of polymer (PMMA) is used as an example. A dual-micro-mechanism rate-dependent constitutive model is used to describe thermo-mechanical response of amorphous polymers below and above glass transition temperature. Material property definitions, evolution of internal state variables, and plastic flow rules are revisited to provide a smooth and continuous transition in material response around glass transition temperature, θg.