Fabrication and Mechanical Testing of the Uniaxial Graded Auxetic Damper.

Hasan Al-Rifaie,Matej Vesenjak,Nejc Novak,Wojciech Sumelka,Zoran Ren

doi:10.3390/ma15010387

Hasan Al-Rifaie, Matej Vesenjak + Show 3 more

Open Access

https://doi.org/10.3390/ma15010387

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Abstract

Auxetic structures can be used as protective sacrificial solutions for impact protection with lightweight and excellent energy-dissipation characteristics. A recently published and patented shock-absorbing system, namely, Uniaxial Graded Auxetic Damper (UGAD), proved its efficiency through comprehensive analytical and computational analyses. However, the authors highlighted the necessity for experimental testing of this new damper. Hence, this paper aimed to fabricate the UGAD using a cost-effective method and determine its load–deformation properties and energy-absorption potential experimentally and computationally. The geometry of the UGAD, fabrication technique, experimental setup, and computational model are presented. A series of dog-bone samples were tested to determine the exact properties of aluminium alloy (AW-5754, T-111). A simplified (elastic, plastic with strain hardening) material model was proposed and validated for use in future computational simulations. Results showed that deformation pattern, progressive collapse, and force–displacement relationships of the manufactured UGAD are in excellent agreement with the computational predictions, thus validating the proposed computational and material models.

Highlights

External dampers are necessary for critical structures which do not have suitable damping facilities to absorb dynamic loads
Special attention is needed for dampers, which have applications in mechanical, civil, and aerospace engineering, e.g., as seismic vibration controllers in multi-story structures [1]
Productions of new auxetic cellular metamaterials (ACM) need designing on the level of computational simulations. Those methods are usually based on the finite element method (FEM), which gives a deep understanding of their behaviours, i.e., vital for evaluating the deformation behaviour and mechanical response of various cellular materials and their potential applications

Summary

Introduction

External dampers (or energy absorbers) are necessary for critical structures which do not have suitable damping facilities to absorb dynamic loads. Productions of new ACM need designing on the level of computational simulations Those methods are usually based on the finite element method (FEM), which gives a deep understanding of their behaviours, i.e., vital for evaluating the deformation behaviour and mechanical response of various cellular materials and their potential applications. The manufacturing of the UGAD consisted of a relatively cheap modified fabrication technique, inspired by Remennikov et al [41] They manufactured large-scale re-entrant auxetic panels by corrugating aluminium sheets into the desired geometry/topology and gluing them using low-functionality polyurethane-based structural adhesive. The main four objectives of this research were: proposing a simplified material model of the tested aluminium alloy (that shows better convergence and more-stable computational simulations); fabricating the UGAD using a non-expensive technique rather than 3D printing; experimental testing of three UGAD samples under quasi-static loading; and building a verified nonlinear finite element model for future applications. FwFiihgguoulrreeeU55.G.EAExxpDpe,eriirnmimceluendntatinal ltgetstehtsientigdnagumsuinpsgeinragbqoaudaqysuia-asnstdai-tsitcthaectoipcmiscptoormens;ps(irboen)sstteieossnttiinntgegstmthineagcthhmirneaeec: ha(auin)xetee:tsi(ctainc) ogtreteshste.inwghtohlee UGAD, including the damper body and the piston; (b) testing the three auxetic cores

Computational Model

Results and Discussion

Patents