Аннотация:The first part of the paper presents the application of the asymptotic averaging method for determining the effective moduli and stress concentration in the B4C/2024Al composite using 2D and 3D x-ray images of the internal structure. The material has a non-periodic structure. The second study concerns an application of asymptotic homogenization to metamaterials. Metamaterials may have some distinctive properties: tension–bending coupling or tension–torsion coupling. Most metamaterials have a periodic structure in Cartesian coordinates. Here it is important to raise the fundamental question regarding the number of periodicity cells, which determines whether the metamaterial is really material or it is a structure. If some property remains to be true for infinite number of cells, then we treat such a metamaterial as real material. On contrary, the metamaterial must be treated just as a structural element, if the same property is valid only for finite number of cells and vanishes when the number of cells approaches infinity.