Micromechanical modeling of smart composites considering debonding of reinforcements

Using the information of the microstructure, this paper presents the development of an incremental constitutive law governing the response of an electro-magneto-thermo-mechanical smart composite. In this development, different shapes of reinforcements that have magneto-electro-thermo-elastic properties that differ from the matrix material are considered. Shapes such as ellipsoidal (spherical, prolate and oblate) particles, elliptical and circular cylindrical fibers, disk and ribbon can be treated provided that the corresponding Eshelby tensor is used. The debonding of the reinforcements from the matrix is also a part of the microscopic process considered. The developed incremental constitutive law not only predicts the macroscopic and microscopic electro-magneto-thermo-mechanical-elastic behavior of composites while considering the debonding process, but it also characterizes their different macroscopic effective properties such as permittivity, permeability, stiffness moduli, pyroelectricity, pyromagnitivity and thermal expansion coefficient in different directions. Moreover, the developed constitutive law is applicable to porous materials and composites with multiple reinforcements and porosities. In the two examples considered below, particular attention is devoted to assessing the effects of both the shape and the concentration of the inclusion and/or porosity and the damage evolution on the multiphysical microscopic and macroscopic behaviors and the effective properties. The first example sheds light on obtaining the macroscopic effective properties, taking into account the piezoelectric BaTiO3 continuous fibers embedded in the piezomagnetic CoFe2O4 matrix. While in the second example, mechanical loading is considered, epoxy is taken as the matrix material and the response of the composite is presented while the evolution of damage in terms of debonding is taking place.