Study on Negative Poisson Ratio and Energy Absorption Characteristics of Embedded Arrow Honeycomb Structure

Wenzheng Liu,Jiachu Xu,Shiqing Huang

doi:10.32732/ase.2020.12.2.47

Abstract

Impact collision exists widely in people's daily life and threatens people's life safety. Negative Poisson's ratio structure has good mechanical properties. Therefore, it is of great significance to design and study the energy absorption structure with negative Poisson's ratio effect. Based on the traditional symmetrical concave honeycomb structure (SCHS) with negative Poisson's ratio, two modified negative Poisson's ratio honeycomb structures are proposed by adding embedded straight rib arrow structure and embedded curved rib arrow structure, which are respectively called embedded straight rib arrow honeycomb structure (SRAH) and embedded curved rib arrow honeycomb structure (CRAH). Through finite element simulation experiment, the negative Poisson's ratio characteristics of two cellular cells were studied and the influence of structural parameters of the cells on the Poisson's ratio was discussed. ANSYS/LS-DYNA was used to analyze the energy absorption of the proposed three cellular structures at different impact velocities. Numerical simulation results show that the SRHS and CRAH have greater stress platform value, specific energy absorption and impact force efficiency than SCHS, indicating that the SRAH and CRAH exhibited better energy absorption efficiency and impact resistance performance.

Highlights

Inspired by the natural honeycomb, researchers have created a positive Poisson's ratio honeycomb structure with the advantages of light weight, excellent energy absorption and high impact resistance, which has been widely used in many fields, including aerospace, architecture and medical
The nominal strain and nominal stress are defined as: εε δδ h σσ where δδ and h is the compressive displacement in the y direction and model of the high, respectively, F is the compression reaction force of rigid plate and model, A is the cross-sectional area of contact cross section between rigid plate and model
Specific energy absorption, compressive force efficiency and platform stress are widely used to evaluate the energy absorption capacity of structures [34,35].The total energy absorption, whose magnitude is equal to the area under the load-displacement curve, represents the sum of the impact energy absorbed by the entire material from deformation to the current state

Summary

Introduction

Inspired by the natural honeycomb, researchers have created a positive Poisson's ratio honeycomb structure with the advantages of light weight, excellent energy absorption and high impact resistance, which has been widely used in many fields, including aerospace, architecture and medical. Compared with the traditional hexagon honeycomb structure, the reentrant hexagon honeycomb structure has better mechanical properties [26,27,28,29], but its low stiffness limits its application in reality It is difficult for the new structure to increase the stiffness of hexagonal honeycomb and ensure that auxetics will not be greatly reduced. Lu et al [31] proposed a new topology concept by adding a narrow ribs into the unit cell of classical re-entrant structure They compared the Young's modulus and Poisson's ratio with the analytical method and the finite element method, and found that the young's modulus of the ribbed structure was significantly higher than that of the re-entrant hexagon structure. Li et al [32] proposed two new 2D re-entrant

Methods

Results

Conclusion