Cuttlebone-inspired honeycomb structure realizing good out-of-plane compressive performances validated by DLP additive manufacturing.

• Cuttlebone-inspired honeycomb with asymmetric sinusoidal walls is first proposed. • Effect of the wall amplitude and gradience on the crushing performances are revealed. • The mechanism of honeycomb is fully studied through FEM and the elastic theory. Inspired by cuttlebone microstructure, this study proposes a novel bionic square-tube cuttlebone-inspired honeycomb (S-CIH) structure prepared by digital light processing (DLP) method. Fifteen configurations of honeycombs of same mass including S-CIH, regular honeycomb (S-RH) and sinusoidal honeycomb (S-SH) structures are evaluated and compared in terms of the deformation behavior and compressive performances under out-of-plane compression, especially energy-absorbing capacity. The results indicate that the S-CIH structure achieves the improved energy absorption 8.859 J/g, over 40 % and 60 % than that of S-RH and S-SH structure with same relative density and mass, respectively. The mechanism analysis of the asymmetric corrugated walls disposed in cross and parallel in S-CIH, reveals that the magnitude of amplitude determines the buckling mode thus folding mode of walls, and the magnitude of amplitude gradient determines whether the whole honeycomb structure can achieve a progressive failure. Optimal structural ratio can enable S-CIH delay the complete failure and improve the long-term failure-resistance. This indicates that S-CIH design has the potential ability to strengthen and toughen other brittle matrix materials, and the cuttlebone-like architecture provides a new biological design of mechanically efficient meta-honeycomb beyond conventional honeycomb structure. [Display omitted] [ABSTRACT FROM AUTHOR]