A hybrid architectural metamaterial combing plate lattice and hollow-truss lattice with advanced mechanical performances

Inspired by the hollow-tube architecture and chambers found in bamboo, we propose a design concept for mechanical metamaterials based on the hybridization of plate lattice and hollow-truss lattice (HPHL) to enhance the mechanical performance of lattice metamaterials in this paper. The design feasibility of HPHL is demonstrated through sample manufacturing using the laser powder bed fusion technique. Quasi-static compressive tests are conducted to investigate the crushing behavior of HPHL. Compared with the typical plate lattice, the HPHL exhibits a more effective crushing region, a higher mean crushing stress and a larger specific energy absorption (SEA). The SEA of HPHL is improved by 53.18% compared with that of the pure plate lattice. Based on the verified numerical simulations, the crushing mechanisms of HPHL are investigated through examining the deformation process and the stress-strain curve. It is found that the incorporation of hollow-truss lattices effectively delays the densification of the plate lattice and provides a more homogeneous and efficient stress distribution in HPHL, leading to higher crushing stress and higher energy absorption efficiency. Moreover, the effects of various design parameters, such as the hollow-truss diameter dT, hollow-truss thickness tT and plate thickness tP, on the mechanical behavior of HPHL are further explored to identify the optimal HPHL and realize the mechanical customization. The bionic hybrid design strategy proposed in this paper paves a new promising route to improve the mechanical performance of lattice metamaterials.