Multiscale simulation and theoretical prediction for the elastic properties of unidirectional fiber‐reinforced polymer containing random void defects

Polymer-matrix composites are widely used in various industries due to their high specific strength and stiffness. However, the void formation is inevitable as a by-product during manufacturing processes, which may have negative effects on its mechanical properties. The purposes of this paper quantitatively evaluate influence voids anisotropic elastic properties provide corresponding theoretical prediction models. Firstly, three-dimensional representative volume elements (RVE) fiber-reinforced composite materials with different fiber contents (36.37%, 45.47%, 50.92%) (1%, 3%, 5%, 7%) established. To obtain directions, periodic boundary conditions applied RVE models subroutines developed by ABAQUS-PYTHON. Secondly, series proposed quickly predict unidirectional fiber/epoxy containing random-sized defects, agree well finite element simulation results. Especially, concise expressions, require only few parameters be input, hence they convenient for engineering application. Both numerical results show that defects an obvious transverse modulus, major Poisson's ratio, out-of-plane shear modulus. When reaches 7%, all mentioned above decrease more than 10% FRPs studied.