Finite element analysis of unidirectional fibrous polymer composites by considering interfacial debonding

A numerical finite element study was performed to obtain the tensile properties of unidirectional fiberreinforced composites containing PP and short glass fiber using a three-dimensional representative volume element (RVE) and ANSYS FEM software. The influences of fiber aspect ratio and interphase volume fraction on the tensile performance of composite were investigated. The initiation and propagation of interfacial crack were simulated based on a bilinear cohesive zone method (CZM) with zero-thickness for mixed mode debonding. FE simulation indicated that the tensile strength of composite reinforced by short glass fiber (SGF) is strongly affected by the interface strength and critical energy release rate of interfacial debonding as well as fiber orientation. It is noticeable that the longitudinal tensile modulus of SGF reinforced composite (E11) is obviously higher than its transvers modulus (E22).The results of FEA indicated, the proposed CZM can be used to simulate the softening mechanism of reinforced composites.