An alternating collinear tubular lattice material with enhanced energy absorption

Tubular lattice materials have garnered significant attention for their exceptional bending and compressive properties. However, conventional simple cubic tubular lattice materials often exhibit premature failure due to the presence of hollow nodes within discontinuous tubes. To overcome this limitation, we propose a novel three-directional alternating collinear tubular lattice material featuring continuous tubes that eliminate hollow nodes. The mechanical performance of this design is investigated through theoretical analysis, numerical simulations, and experimental validation. At low relative densities, the deformation behavior is predominantly governed by the vertical continuous tubes, which contribute approximately 95% and 91% to the overall stiffness and strength of the lattice, respectively—representing enhancements of 2.3-fold and 1.6-fold compared to the conventional design. As the relative density increases, material overlap and tube coupling effects become significant, with horizontal tubes providing displacement restraint and buckling control for vertical tubes, thereby further enhancing structural performance. At high relative densities, the synergistic action of vertical and horizontal tubes results in stable plastic bending deformation within the ACT lattice. The proposed lattice achieves a normalized yield strength 29% higher than that of the stiffest smooth shell-like lattice structure at a relative density of 0.5, while also demonstrating superior specific energy absorption at a relative density of 0.3. These results underscore its potential for applications in load-bearing and energy absorption.