Low porosity metallic periodic structures with negative poisson's ratio

Auxetic behavior in low porosity metallic structures is demonstrated via a simple system of orthogonal elliptical voids. In this minimal 2D system, the Poisson's ratio can be effectively controlled by changing the aspect ratio of the voids. In this way, large negative values of Poisson's ratio can be achieved, indicating an effective strategy for designing auxetic structures with desired porosity. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim