Characterization of three-dimensional braided carbon/Kevlar hybrid composites for orthopedic usage

Three-dimensional (3D) braided carbon/Kevlar hybrid composites were fabricated by an RTM-aided vacuum solution impregnation plus in situ polymerization. The load-displacement behaviors, flexural properties, impact property, and shear strength of these 3D braided hybrid composites were studied as a function of Kevlar/carbon ratio. Composites of six different relative Kevlar fiber contents (0%, 20%, 40%, 60%, 80%, and 100% by volume) were prepared and characterized. Environmental scanning electron microscopy (ESEM) was used to examine the fracture surfaces of the hybrid composites. Hybrid effects for strain, flexural strength and modulus, shear strength, and impact property of the 3D braided composites were assessed. It was found that hybridization provided high flexural strength and modulus for the 3D braided composites. It is concluded that hybridization is an effective way of tailoring the properties of the 3D braided composites for orthopedic applications.