Fabrication and Interlaminar Shear Strength of 3D-Printed CCF-PEEK Rotationally Curved Structures

Traditional continuous fiber 3D printing technology has primarily focused on the fabrication of planar structures, with relatively insufficient research on curved composite components. To address the key technical challenges in the continuous fiber-reinforced 3D printing of rotationally curved components, this study conducted systematic research on printing equipment design, path planning methodologies, and interlaminar performance optimization using carbon fiber-reinforced polyether-ether-ketone (CCF/PEEK) prepreg filament. A multi-degree-of-freedom curved-surface printing system based on a six-axis robotic arm was developed to overcome the geometric limitations of traditional three-axis equipment. A cylindrical surface path layering algorithm based on STL models was proposed, achieving full-process digital manufacturing of curved components. Through orthogonal experiments and response heatmap analysis, it was clarified that printing speed and printing temperature are the key process parameters affecting interlaminar shear strength, with printing speed being the most influential. The optimal parameter combination (printing speed 0.8 mm/s, printing temperature 380°C, mold temperature 160°C, layer thickness 0.2 mm) improved the interlaminar shear strength to 55.36 MPa. Microscopic morphology analysis demonstrated that optimized thermal input conditions effectively enhance the fiber-resin interfacial bonding quality. This research provides valuable process references for the additive manufacturing of lightweight and high-strength curved components.