Exploring Bionic Twisted TPMS Designs for Improved Energy Absorption

Triply periodic minimal surface (TPMS) lattice structures have emerged as a promising class of customizable mechanical metamaterials owing to their outstanding potential in lightweight design and multifunctional engineering applications. However, previous studies have mainly concentrated on global parameters such as wall thickness, cell size, and periodicity, while the local deformation and pre-deformation characteristics of unit cells, particularly the twist effects along specific directions, have not been systematically investigated. To address this gap, a bioinspired twisted design strategy was proposed in this study, in which controllable pre-twist was introduced along the build direction to tailor the energy absorption behavior of lattice structures. Twisted lattice specimens with different twist angles were fabricated using selective laser melting, and their mechanical properties were comprehensively examined through numerical simulations and experimental validation. The results indicate that the mechanical response of TPS under axial compression is strongly influenced by the twist angle, with its EA and SEA achieving maximum increases of 22.18% and 22.64%, respectively, when the twist angle increased from 0° to 180°. The TGS structure exhibited a complementary two-stage stress–strain response, whereas the TIS structure became more susceptible to deformation with increasing twist angle, leading to a maximum ULC improvement of 15.5%. The proposed twisted design thus provides a novel pathway for optimizing lattice structures by balancing energy absorption capacity and structural stability.