Design, fabrication, and characterization of 3D printed continuous fiber composite lattice structures via discrete insert-module assembly

Abstract

3D printed continuous fiber reinforced composite lattices offer compelling advantages for lightweight structures, but current approaches face challenges in manufacture and mechanical characterization. We introduce a discrete insert-module assembly process and a lattice topology tailored to continuous fiber 3D printing. A closed-form theoretical model and a high-fidelity finite element framework are established and validated against quasi-static compression tests. Results show that complex spatial lattices can be fabricated by assembling planar inserts, and that the proposed theory and simulations predict stiffness and strength within ∼10% of experiments. Compared to reported 3D printed composite lattices, the present structures achieve competitive mechanical properties and higher continuous fiber load-bearing efficiency when normalized by continuous fiber volume fraction, indicating effective alignment of continuous fibers with principal load paths. These findings provide both experimental evidence and a predictive toolkit for engineering spatial structures using 3D printed continuous fiber composites.