A Thermo-Micromechanical Theory for Effective Elastic Constants of Composite Materials

A thermo-micromechanical approach is presented to estimate the constitutive response of fiber reinforced composites. The approach is based upon thermodynamic considerations involving Helmholtz and Gibbs free energies and micromechanical considerations involving strain and stress fields associated with the fiber and matrix components. The results obtained for principal elastic constants for polymer and metal matrix composites show good correlation with the available experimental data and with other popular models. The parametric results include cases of fiber anisotropy and relative stiffness variation between fiber and matrix materials.