Enhanced interlaminar shear strength of CCF/PEEK composites by rotary 3D printing with conformal infrared preheating and dual-roller hot pressing

Continuous carbon fiber reinforced polyetheretherketone (CCF/PEEK) composites have attracted increasing attention in aerospace and high performance applications owing to their superior mechanical and thermal properties. However, additive manufacturing of CCF/PEEK structures with rotational geometries remains difficult due to the high melt viscosity and semi-crystalline nature of PEEK, as well as the lack of effective interfacial bonding strategies for curved surfaces. In this study, a rotary 3D printing process is developed to enable high quality fabrication of CCF/PEEK components with enhanced interlayer adhesion. The system integrates a mold conformal infrared heating module with dual hot rollers, providing continuous thermo-mechanical assistance during deposition. The infrared module ensures uniform surface temperature along the curved deposition path, while the front and rear rollers sequentially induce primary and secondary thermal compaction, promoting resin squeeze flow, percolation, and intimate bonding. Naval Ordnance Laboratory (NOL) rings were fabricated under different printing heights and preheating conditions. Results show significant improvements in surface morphology, crystallinity, and interfacial strength. Specifically, the interlaminar shear strength increased by 117 % at 200 °C preheating and 0.1 mm layer height. This work demonstrates a robust pathway for performance oriented additive manufacturing of continuous fiber reinforced composites with curved geometries.