Fiber reinforced epoxy composites for femur fractures: a mechanical investigation

Abstract Femur fractures, often resulting from trauma or osteoporosis, pose significant challenges due to their effect on mobility and life quality. Metallic implants like titanium and stainless steel, despite their strength and biocompatibility, present problems related to stress shielding, altered biomechanics, and limitations in diagnostic imaging. This research suggests the use of biocompatible epoxy composites fortified with kevlar fibers (KF), carbon fibers (CF), hybrid fibers, and flax as potential replacements for metallic implants to address these issues. Our examination of the biomechanical reactions of these composites under tensile and flexural stresses revealed that kevlar fiber composites demonstrated superior performance, exhibiting exceptional mechanical properties with a maximum tensile strength of 283.5 MPa and flexural strengths of 53 MPa and 90.4 MPa for the first and second modes, respectively, at a 24% volume fraction. While flax fibers offer the advantage of being natural, their performance was found to be subpar. Carbon and hybrid fiber composites showed performance similar to flax but inferior to kevlar. Interestingly, the inclusion of kevlar in hybrid composites enhanced performance compared to carbon composites. All composites experienced a 50% reduction in ductility when transitioning from the first to the second flexural mode, but this was offset by a significant increase in flexural strength. These findings suggest that kevlar fiber-reinforced composites, despite addressing the problems associated with metallic implants, show promise as an alternative material for femur implants due to their superior mechanical properties. Further research is required for clinical application to optimize fiber mixtures, enhance composite structures, and assess in vivo biocompatibility.