Compressive response and energy absorption of additive manufactured Ti-6Al-4V triply periodic minimal surface honeycomb structure

This study proposed a design method of honeycomb structure based on triply periodic minimal surfaces (TPMS), namely gyroid-honeycomb. The honeycomb samples were fabricated by selective laser melting (SLM) with Ti6Al4V (TC4) material. Through the uniaxial quasi-static compression tests and numerical simulations, the mechanical responses and energy absorption capability of honeycomb structures under different compressive velocities were investigated. Compared with conventional truss-honeycomb structure, the gyroid-honeycomb exhibited reduced stress fluctuation and enhanced energy absorption capability under in-plane compressive direction. Particularly, gyroid-honeycomb also demonstrated a superior energy absorption capability under both low and high compressive velocities. According to the scanning electron micrograph (SEM) image of the fracture surface, the gyroid-honeycomb exhibited a unique buckling failure mode along with a large plastic deformation and negative Poisson's ratio. The different compressive responses can be attributed to the distinct stress distribution in gyroid-honeycomb according to the simulation results. Notably, the gyroid-honeycomb structure displayed a remarkable capacity for energy absorption across various compressive velocities. These findings provide valuable insights into the application of the novel TPMS-based honeycomb structures in enhancing the crashworthiness protection for vehicles.