Crashworthiness Design of 3D ‐Printed Short Carbon Fiber Reinforced Polyamide Origami Sandwich Tubes

ABSTRACT Driven by the demand for lightweight manufacturing, composite materials are increasingly substituting traditional metals in thin‐walled structures, simultaneously reducing weight and enhancing overall mechanical performance. This study presents a novel sandwich energy‐absorbing tube fabricated by 3D printing PA‐CF15, consisting of inner and external hexagonal straight tubes and a central origami core. The unique folding kinematics of the origami pattern are exploited to orchestrate the deformation behavior. The central origami core incorporates three typical configurations: the Kresling pattern, the full‐diamond pattern, and the pre‐folded pattern. Selective optimization, variable‐thickness gradient design, and multi‐cell configuration design strategies were introduced. The results show that Kresling origami sandwich tube (KOST) exhibited an energy absorption (EA) enhancement of 154% compared with the linear superposition of its constituent parts. Also, the full‐diamond origami sandwich gradient tube (FOSGT) achieved the most balanced overall performance, with EA increasing by 144% and specific energy absorption (SEA) by 77% relative to the FOST. Selective optimization design has proven highly effective in reducing mass and mitigating peak load. In addition, there is an optimal cell configuration for different origami. This study validated the synergistic effects of geometric configuration and material reinforcement, providing a reference for the crashworthiness of composite sandwich structures.