Effect of Splitting of Polymer Fibers on the Strength of Unidirectional Composites

Abstract

With the example of Aramid fibers, it is shown that the model of acumulation of fiber breaks in composites cannot explain their observed tensile strength exceeding that of unimpregnated Aramid fibers. The model of longitudinal splitting of fibers proposed by Wagner, with account of fiber-matrix interaction, is based on the idea that the break of fibers begins at great strains owing to their interaction with the matrix. This model better describes the failure of composites with anisotropic fibers having an internal fibrillar structure. The results obtained can also be used for other types of fibers with an internal microstructure.