Dynamic Capillary-Driven Additive Manufacturing of Continuous Carbon Fiber Composite

Additive manufacturing (AM) of lightweight and energy-efficient composites using continuous carbon fibers and thermosetting polymers offers great opportunities for advancing composite manufacturing with design flexibility, reliability, and repeatability. However, to date there have been few AM techniques reported to process continuous fiber-reinforced thermosetting composites. Here, we report a dynamic capillary-driven AM approach with a controllable viscosity and degree of curing of polymer to enable its fast and near-simultaneous infusion and curing to implement in situ solidification of composites into arbitrary shapes. Using the technique, we developed a robotic system consisting of a uniquely designed printing head and an automated robot arm, yielding a 3D printer that enables us to print a composite on 2D and 3D sub-strates or in free space. The printed composite had high fiber volume fraction (58.6%) and degree of curing (95%) with high mechanical strength (810 MPa) and modulus (108 GPa).