A statistical approach for the evaluation of mechanical properties of silica/epoxy nanocomposite: Verification by experiments

In this study, we have developed a global statistical approach for the characterization of the elastic properties of silica/epoxy nanocomposites. In this approach, we selected a series of scanning electron microscopy (SEM) images of a nanocomposite sample as a representation of the microstructure (representative volume element, RVE). In the next step, we used statistical continuum theory by strong-contrast method for the evaluation of the effective elastic modulus of each SEM image. In the final step, we used 2-dimensional (2D) finite element modeling for the evaluation of the effective elastic modulus of the nanocomposite sample consisting of the preselected set of SEM images (RVE). In addition to the global statistical approach, we have also developed a 3-dimensional (3D) finite element model with the assumption of perfect dispersion of silica nanoparticles inside the epoxy matrix. Comparison between the experimental measurements for the nanocomposite elastic modulus and modeling results by the global statistical approach reveals a fine agreement. We also found that the predictions by the 3D finite element method with perfect dispersion of particles underestimate the experimental results.