Mechanical Characterization of 3D Printed Honeycombs with Planar Ribs for Enhanced Energy Absorption

Additive manufacturing technology enables the fabrication of complex structures with intricate geometries. Due to the vast available design space enabled by additive manufacturing, there are many opportunities for discovering novel designs, such as mechanically advantageous honeycomb metamaterials. Herein, incorporation of internal planar ribs into conventional square honeycomb structures is implemented to enhance their energy absorption (EA) capabilities. An integrated experimental and computational approach is conducted to design, fabricate, test, and model structures through finite element analysis for validation and tradeoff assessment. Results demonstrate a significant enhancement in specific EA for honeycombs with rib reinforcements. A single‐rib improved EA by 2.6 times, while adding a second rib further improved EA to 4.5 times with minimal increases in relative density (less than 7%) compared to conventional honeycombs. Finite element analyses are used to simulate the mechanical response of each honeycomb, with demonstrations of added ribs improving consistency of symmetric displacement throughout the structure. Radar plots highlight the advantageous mechanical properties of double‐rib structures for crashworthiness metrics. These findings contribute to the understanding and demonstration of novel 3D printed honeycombs with planar ribs that serve as energy absorbing materials for wide‐ranging engineering applications.