Mechanical and failure characteristics of novel tailorable architected metamaterials against crash impact

Abstract

The mechanical properties of cellular materials cannot be on-demand tuned after manufacture, and the crashworthiness of existing tailorable metamaterials is often limited. To combine desirable and tailorable crashworthiness with ease of manufacture, novel tailorable architected metamaterials that can be flexibly assembled using discrete modules are proposed in this study. The specimens are manufactured by 3D printing method, and matched finite element analysis is conducted using ABAQUS. The proposed metamaterials achieve specific energy absorption and the maximum efficiency respectively 76.1% and 39.9% larger than the existing self-locked systems. Moreover, the metamaterials exhibit critical failure characteristics such as omnidirectional self-locking capability and imperfection insensitivity. Furthermore, 3D expansion capability allows them to adapt to complex protective requirements. Finally, impact experiments have been conducted on a complex-shaped metamaterial specimen made of thermoplastic polyurethane (TPU) to showcase all the aforementioned advantages. This research paves new avenues for designing high-performance and multifunctional protective structures.