In-plane dynamic crushing and energy absorption capacity of self-similar hierarchical honeycombs

Abstract

The in-plane dynamic crushing behavior and energy absorption capacity of self-similar hierarchical honeycombs under different impact velocities are numerically studied using ANSYS/LS-DYNA. First, the hierarchical honeycomb models with uniform cell-wall thickness are constructed by replacing every three-edge structure nodes of a regular honeycomb with smaller self-similar hexagons of the same orientation. The respective influences of hierarchical parameters, bulk materials, and impact velocities on the macro-/micro-deformation behaviors, the dynamic strength, and the specific absorbed energy of hierarchical honeycombs are explored in detail. The results show that the crushing strengths and energy-absorbing capacities of honeycombs significantly improve when adding the hierarchy into conventional cellular structures. The variation of hierarchical parameter changes the local dynamic evolution of stress waves, which further results in different macro-/micro-deformation properties. Through the proper choice of hierarchical parameters and bulk materials, the optimal crushing strength and the maximum absorbing energy could be obtained.

The in-plane crashworthiness of multi-layer regularly arranged circular honeycombs

“…As mentioned in section ''Most appropriate strain,'' all s-e curves have four different phases: linear elastic phase, yield phase, flat plateau stress phase, and densification phase, which are similar to the curve patterns of other 2D honeycombs, [28][29][30][31][32][33][34][35][36][37][38][39][40][41] even though the s-e curves have different characteristics at different crushing velocities. Mean quasi-static and dynamic plateau stresses are discussed in detail in section ''Mean plateau stress.''…”

“…Owing to the advantages of FE simulations over experiments, the FE numerical method has been solely and widely used in the investigations of 2D honeycombs. [28][29][30][31][32][33][34][35][36][37][38][39][40][41] The existing investigations have shown that the configuration parameters and crushing velocity affect the dynamic behaviors of 2D honeycombs. The typical configuration of the MRACHs (with 9 3 9 cells in directions x 1 and x 2 ) is shown in Figure 1 In this article, the in-plane (direction x 2 or x 1 in Figure 1) crashworthiness of MRACHs is investigated numerically using the explicit FE analysis software, ANSYS/LS-DYNA, at the crushing velocities 1-250 m/s.…”

Deformation mode and energy absorption of polycrystal-inspired square-cell lattice structures

“…Then, the effects of the cell orientation angle and the cell size on the mechanical properties were explored [16][17][18] . So far, there have been a considerable number of studies on the crushing behaviors of regular honeycombs, especially for the regular hexagonal honeycombs, with theoretical, numerical and experimental methods [19][20][21][22][23] .…”

“…For regular and irregular hexagonal grids and circular grids, a number of researches have been conducted. In recent years, increasing interest has been paid to the novelcell grids and the composite grids which show enhanced EA capacity [18][19][25][26][27] . Although there exist considerable theoretical and numerical studies for the type grids [28][29][30][31][32] , few efforts are paid to the effect of orientation parameters on the initial peak force and the EA for the square-cell grids.…”

“…Fig 19. The deformation mode of the 0 • -45 • -30 • -15 • configuration quad-crystal lattice (color online)…”