Influence mechanism of cell-arrangement strategy on energy absorption of dual-phase hybrid lattice structure

Structural design enables lattice structures to have superior mechanical performance. Currently, most design ideas are derived from bionics or crystal structures, which is an inefficient design method because simplification and optimization are necessary before converting microstructures to macro lattice structures. In this paper, a new design method is proposed based on directly controlling the collapse behavior of hybrid lattice structures without imitating any existing structures. A novel dual-phase hybrid lattice structure featuring a coordinated deformation mode is designed, and the underlying mechanism of the coordinated deformation is revealed. A series of hybrid lattice structures composed of octet-truss and modified (MOD) re-entrant hexagonal cells are proposed to analyze various design strategies. The finite element (FE) simulations validated by experiments are carried out, aiming to contrast and analyze the collapse modes and energy-absorbing performance. Simulation results demonstrate that the hybrid lattice structure with an appropriate cell arrangement can induce coordinated deformation, resulting in superior energy-absorbing performance. The mechanism driving the coordinated deformation is revealed to be related to the diversity of node connectivity and the complexity of node distribution.