The Elastic Uniaxial Properties of a Center Symmetric Honeycomb with Curved Cell Walls: Effect of Density and Curvature

Abstract

We propose in this paper analytical and numerical models that describe the in‐plane uniaxial elastic properties (Young's moduli and Poisson's ratios) of a honeycomb structure with curved walls. We perform a parametric analysis of the mechanical performance of this honeycomb also by taking into account the different types of deformations acting inside the cell walls. The curved wall honeycomb possesses higher magnitudes of the Poisson's ratio ν12 in the auxetic configuration compared to classical center symmetric configuration with straight cell wall. The presence of the curvature also allows creating configurations with positive Poisson's ratio even for negative internal cell angles, and makes this honeycomb design attractive for mechanical tailoring.

Auxetics and Other Systems of Anomalous Characteristics

“…The in‐plane homogenised engineering constants of centersymmetric honeycombs with curved cells are detailed in the paper The elastic uniaxial properties of a center symmetric honeycomb with curved cell walls: effect of density and curvature by Harkati, Daoudi, Abaidia, and Bezazi The paper introduces a series of analytical and Finite Element simulations to describe the uniaxial properties. The presence of curved cells walls appears to amplify the negative Poisson's ratio effect in classical ‘butterfly’ honeycomb configurations compared to their straight ligaments version.…”

Out-of-plane elastic constants of curved cell walls honeycombs

“…The in-plane elasticity modulus of a curved-walled cell was studied by Balawi and Abot [24] using analytical and numerical means and correlated with the experimental results for aluminum honeycomb cells. Analytical and numerical models describing the uniaxial elastic properties in the plane (Young's moduli and Poisson's ratio) of a honeycomb structure with curved walls have been studied by Harkati et al [28].…”

In-plane elastic constants of a new curved cell walls honeycomb concept

“…Several research studies on such systems have been carried out in recent years, particularly about tailored two-dimensional honeycombs. Asymptotic homogenization constitutes a means to replace full-scale simulations for predicting the equivalent mechanical properties of the lattices [3][4][5][6][7][8][9].…”

“…1(a)presents the configuration investigated in this work, in which the sharp edge corners are replaced by rounding of radius r.Fig. 1(b)shows a previous multi-re-entrant configuration evaluated by some of the Authors[2][3][4][5], whileFig. 1(c)is related to the baseline centresymmetric honeycomb structure[1].…”