Innovative Biomechanical Design and Performance of Carbon Fiber-Thermoplastic Implants via Additive Manufacturing

This study explores the potential of 3D-printed carbon fiber-reinforced thermoplastic composites, specifically Nylon and PEEK, as advanced materials for medical implants. Fabricated using fused filament fabrication (FFF), these implants were evaluated against conventional Ti-6AL-4V titanium alloy counterparts through a combination of experimental analysis and finite element method (FEM) simulations. The novel designs of discontinuous carbon fiber-PEEK and continuous carbon fiber-Nylon composites exhibited enhanced performance, reducing screw pull-out force by nearly 50% relative to Ti-6AL-4V. Furthermore, the thermoplastic composites demonstrated significantly higher bio-elastic coupling strain energy density (SED), indicating superior capacity to promote bone healing and callus formation. A comprehensive multi-criteria evaluation-including metrics on screw loosening, bone remodeling, and resorption-revealed that the 3D-printed composites outperformed titanium by 33%-65%. These results provide design guidelines for FFF 3D-printed composite implants, offering considerable promise as customizable and effective alternatives to conventional metal implants.