Numerical Investigation on Dynamic Crushing Behavior of Auxetic Honeycombs with Various Cell-Wall Angles

Abstract

Auxetic honeycombs have proven to be an attractive advantage in actual engineering applications owing to their unique mechanical characteristic and better energy absorption ability. The in-plane dynamic crushing behaviors of the honeycombs with various cellwall angles are studied by means of explicit dynamic finite element simulation. The influences of the cell-wall angle, the impact velocity, and the edge thickness on the macro/microdeformation behaviors, the plateau stresses, and the specific energy absorption of auxetic honeycombs are discussed in detail. Numerical results show, that except for the impact velocity and the edge thickness, the in-plane dynamic performances of auxetic honeycombs also rely on the cell-wall angle. The "> <"-mode local deformation bands form under low-or moderate-velocity impacting, which results in lateral compression shrinkage and shows negative Poisson's ratio during the crushing. For the given impact velocity, the plateau stress at the proximal end and the energy-absorbed ability can be improved by increasing the negative cell angle, the relative density, the impact velocity, and the matrix material strength. When the microcell parameters are the constant, the plateau stresses are proportional to the square of impact velocity.

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.…”

Using Finite Element Approach for Crashworthiness Assessment of a Polymeric Auxetic Structure Subjected to the Axial Loading

“…The effect of cell-wall alignment on the dynamic responses of a re-entrant honeycomb structure was studied by Zhang et al, [ 23 ]. It was recognized that increasing the impact speed, cell angle and relative density leads to increasing the crashworthiness capability of the auxetic structure.…”

The Development of a New Shock Absorbing Uniaxial Graded Auxetic Damper (UGAD)

“…Examples of cellular geometries, that give auxetic behaviour, are double arrow-head [33], re-entrant [34], chiral [35], and rotating rigid units [36]. They are used to produce foams or auxetic cellular metals, for a wide range of applications, such as aerospace, biomedical and military engineering [37].…”