A New Interfacial Model for Transverse Mechanical Properties of Unidirectional Fiber Reinforced Composites

Transverse mechanical properties play an important role in the study of fiber reinforced composite materials. An experimental and numerical study on mechanical properties and damage behavior of unidirectional fiber reinforced composites under transverse load is presented. The quasi-static tensile and compressive tests were carried out to obtain mechanical properties of unidirectional fiber reinforced composites under transverse tension and compression. The fracture morphologies of the specimens were observed by scanning electron microscopy (SEM) to reveal their distinct damage mechanism. Considering the effects of interface, a new interfacial model is proposed. Two representative volume elements (RVEs) of basic and interfacial models are established for comparison analysis. The predicted results agree well with the experimental data. The introduction of interfacial layer has little effect on the prediction of transverse modulus, but can improve the accuracy of the predicted transverse strength. The fiber volume fraction has a great influence on the transverse mechanical properties of unidirectional fiber reinforced composites. As the fiber volume fraction increases, its transverse modulus increases, but both the transverse strength and the ultimate strain decrease.