Crashworthiness of antiprism thin-walled structures under quasi-static and dynamic loading

• Antiprism tube introduces a novel Four Edges–Three Faces (FETF) geometry. • FETF enables a new failure mode unlike traditional Three Edges–Two Faces (TETF). • Optimal energy absorption at 1:1 width–height and 20:1 width–thickness ratios. • Antiprism tube shows superior impact resistance and longer effective stroke. This study explores the quasi-static and dynamic crushing behavior of a novel antiprism thin-walled structure designed to enhance energy absorption for crashworthiness applications. Unlike conventional cylindrical, polygonal, and origami-inspired tubes, which do not fully exploit wall folding to generate plastic hinges, the antiprism configuration promotes the formation and propagation of multiple plastic hinge lines, enabling stable progressive collapse and extended plateau stages. The structures were fabricated from 316L stainless steel using laser powder bed fusion and evaluated through quasi-static compression, Split Hopkinson Pressure Bar tests, and finite element simulations with the Johnson–Cook model. Compared with conventional counterparts of equal mass and thickness, the antiprism tubes achieved 6.4–14 % higher specific energy absorption (SEA), 7–79 % higher crushing force efficiency (CFE), and 7–68 % lower undesired load-carrying capacity (ULC). Under dynamic impact, they also exhibited the lowest initial peak crushing force. These results highlight the antiprism design as a lightweight and efficient solution for energy-absorbing components in sandwich panels and protective liners.