Thermomechanical Modeling of Irradiated Polymer Composites

Abstract

Thermoelastic models are presented to evaluate constitutive response of fiber-reinforced polymer composites subjected to irradiation and temperature exposure. These models are based upon thermodynamic considerations involving Helmholtz and Gibbs free energy functions, and micro-mechanical models involving Eshelby's modified approach. The proposed union between the energy functions and micro-mechanics provides a unifying framework that can deal with the potential property changes in fibers, matrix and at the fiber-matrix interface. The results for a graphite/epoxy (T300/934) composite show a good agreement with the available experimental data. The parametric study for all the principal elastic constants involving matrix stiffening as well as matrix softening exhibit a number of interesting results.