Optimal arrangement of reinforcement in composites

In the paper the problem of the optimal arrangement of the reinforcement in particulate reinforced composites is considered. The criterion of the optimization is the maximization of the stiffness of composites represented by the effective elastic Young modulus. The coupled boundary and finite element method (BEM/FEM) is used to model and analyze representative volume elements (RVEs) of the material. A matrix is modelled by the BEM and reinforcement by the FEM by means of beam finite elements. The optimization problem is solved by the evolutionary algorithm. In numerical examples, composites with aligned and uniformly distributed reinforcement in the matrix are studied. The assumed material properties and the dimensions of constituents are typical for nanocomposites with single and two-layer platelet-like particles, however, the method can be used for different kinds of particulate composites. As a result of the optimization, an improvement of the stiffness is obtained in comparison with the initial microstructures. The presented approach allows the efficient optimization of both structures on a macro level and the microstructures of materials by analyzing RVEs.