Lateral crushing behavior of tubular lattice structures with triply periodic minimal surface architectures

Tubular lattice structures had attracted significant attention due to their remarkable mechanical performance and lightweight, but there had been few research on their lateral crushing behaviors. In the present work, a novel tubular lattice structure with triply periodic minimal surface (TPMS), named TPMS-T, was manufactured to examine its energy absorption characteristics under lateral crushing through experiments and finite element (FE) simulations, with three types of unit-cell configurations considered for comparison. The numerical predictions of deformation modes and energy absorption responses were in good agreement with the corresponding experimental results. The energy absorption characteristics of three types of TPMS-T were further compared against the single circular tube (SCT) and typical nested tube systems with the same mass and outer size. It was found that TPMS-T exhibited superior crashworthiness performance than the corresponding SCT and typical nested tube system counterparts. The specific energy absorption (SEA) of three types of TPMS-T exceeded that of corresponding SCT by 70% to 133%, and fourfold-tube nested system (FT) by 24% to 61%, respectively. The influence of the relative density, tube thickness and tube outer diameter on the crushing behaviors of TPMS-T was numerically investigated to further understand the crushing mechanism of TPMS-T under lateral crushing. Results showed that the energy absorption performance exhibited an increase trend with increasing the relative density, and crashworthiness indicators could be expressed as a power function of the relative density. Moreover, the tube thickness and tube outer diameter had a large influence on the energy absorption capacity of TPMS-T. Finally, the multi-objective optimization design was further performed to obtain optimized TPMS-T configurations subjected to lateral crushing. The present work was expected to provide researchers and engineers with insights into the design of TPMS-T for structural crashworthiness applications.