Stabilized and efficient multi-crushing properties via face-centered hierarchical honeycomb

The undesirable resistance to multi-crushing loads limits the development of regular honeycomb structures in advanced engineering fields. Therefore, a novel hierarchical strategy, namely face-centered hierarchical strategy, is proposed to improve the multi-crushing properties of honeycombs. The honeycombs with the face-centered hierarchical network are manufactured by selective laser melting to test their energy absorption mechanism against the oblique crushing load. The multi-crushing properties of face-centered hierarchical honeycomb (FCHH) are explored by a numerical investigation. The carrying capacity and energy absorption of the FCHH decrease with the increasing crushing angle. The parameter configuration design indicates that the hierarchy order has a positive effect on the multi-crushing resistance of the FCHH. The face-centered hierarchical network not only provides the strong lateral support, improving the collapse of the honeycomb, but also reduces the folding wavelength, improving its material utilization. Specifically, the specific energy absorption and crushing force efficiency of the FCHH improve by 27.65 % and 30.83 % respectively as the hierarchy order increases from 1 to 3 at the crushing angle of 30 degrees. Furthermore, when the thickness gradient factor is close to 1, the FCHH obtains a more reasonable material distribution to resist the oblique crushing load. Compared with other hierarchical honeycombs for the oblique crushing resistance, the FCHH demonstrates a more stable carrying process and more efficient energy absorption. This research expects to propose a promising reinforcement strategy to guide the design of multi-crushing properties for honeycombs.