Mechanical properties and energy absorption of 3D printed double-layered helix honeycomb under in-plane compression

Bio-inspired structural design was considered as a promising strategy to improve the mechanical performance and energy absorption of lightweight cellular materials. In this study, a novel double-layered helix honeycomb (DLHH) was designed and manufactured through 3D printing technique. The in-plane mechanical property and energy absorption capability of the novel DLHHs were investigated with a combination of experiments and simulations. The results showed that, by introducing double-layered helix configuration in unit cell, the mechanical property and energy absorption capability were effectively enhanced, while obvious changes in the deformation process were also found compared to regular honeycomb (RH). For example, the DLHHs reveal a 45% enhancement in the strength and a 200% enhancement in the specific energy absorption. In addition, the experimental and simulation results revealed that the cells of DLHH were deformed and collapsed layer-by-layer along the compressive direction, while the cells of RH were deformed and collapsed layer-by-layer along the shear direction. The findings presented open a new avenue to engineer honeycomb structures with enhanced mechanical properties and energy absorption capability, finding applications for various applications, such as automobiles and aircrafts.