Mechanically Efficient Cellular Materials Inspired by Cuttlebone.

Cellular materials with excellent mechanical efficiency are essential for aerospace structures, lightweight vehicles, and energy absorption. However, current synthetic cellular materials, such as lattice materials with a unit cell arranged in an ordered hierarchy, are still far behind many biological cellular materials in terms of both structural complexity and mechanical performance. Here, the complex porous structure and the mechanics of the cuttlebone are studied, which acts as a rigid buoyancy tank for cuttlefish to resist large hydrostatic pressure in the deep-sea environment. The cuttlebone structure, constructed like lamellar septa, separated by asymmetric, distorted S-shaped walls, exhibits superior strength and energy-absorption capability to the octet-truss lattice and conventional polymer and metal foams. Inspired by these findings, mechanically efficient cellular materials are designed and fabricated by 3D printing, which are greatly demanded for many applications including aerospace structures and tissue-engineering-scaffold. This study represents an effective approach for the design and engineering of high-performance cellular materials through bioinspired 3D printing.