Tensile and interfacial properties of unidirectional flax/glass fiber reinforced hybrid composites

This paper studied the mechanical behaviors of unidirectional flax and glass fiber reinforced hybrid composites with the aim of investigation on the hybrid effects of the composites made by natural and synthetic fibers. The tensile properties of the hybrid composites were improved with the increasing of glass fiber content. A modified model for calculating the tensile strength was given based on the hybrid effect of tensile failure strain. The stacking sequence was shown to obviously influence the tensile strength and tensile failure strain, but not the tensile modulus. The fracture toughness and interlaminar shear strength of the hybrid composites were even higher than those of glass fiber reinforced composites due to the excellent hybrid performance of the hybrid interface. These macro-scale results have been correlated with the twist flax yarn structure, rough surface of flax fiber and fiber bridging between flax fiber layers and glass fiber layers.