Experiment and numerical investigation on bio-inspired tube-plate hybrid lattice structure with dual-stress plateaus and enhanced energy absorption
Mingzhi Wang, Yinzhu Wang, Jianjun Wu, Weidong Wang
Abstract
Lattice structures have drawn significant interest owing to their exceptional mechanical properties, e.g. lightweight, strong, and tough performance. Here, inspired by the biostructure of the beetle elytra, a new tube-plate hybrid lattice structure (TPHL) is proposed. The TPHL lattice specimens are fabricated by the selective laser melting (SLM) technique, and the compression mechanical properties are analysed. The compression responses of the TPHL are compared with conventional Octet (OCT), simple cubic (SC), and simple tube (TUBE) lattice structures. An optimisation model is developed to further improve the energy absorption characteristics. The TPHL lattice structure exhibits maximum 50.30% (relative density is 0.10) higher specific energy absorption (SEA) than SC pure plate lattice, and maximum 42.25% (ρ¯=0.18) higher specific energy absorption than OCT pure plate lattice. The novel lattice structure shows the transition of the deformation modes and dual energy-absorbing plateaus. The enhanced energy absorption is mainly ascribed to the interaction of the cross-assembled tubes and plates in the second plateau. Besides, the configuration of the TPHL lattice structure after optimisation demonstrates significantly enhanced energy absorption characteristics. The bioinspired design strategy and potential mechanical mechanism provide useful guidance for designing lattice structures with exceptional energy absorption properties.