Fig. 1: Auxetic behaviour on demand.
From: A three step recipe for designing auxetic materials on demand
a Shows the uniaxial compression test of three auxetic designs, each of them generated with our proposed algorithm. More on Supplementary Movie 1 and 2. Scale bars 1 cm. The colormap on the finite element simulations shows the sections of minimum and maximum stress in the elastic material. Clearly the stress is focused on the joints between polygons. b The Poisson’s ratio of each configuration as a function of the strain. “Exp” and “FE” refer to experimental and finite element simulations results respectively. The experimental error bars show the standard deviation from measuring each polygon’s position. c Comparison between two bigger Penrose structures with thin and thick bonds, showing the capabilities of tuning the Poisson’s ratio as a function of the bending energy. These bigger structures can be found on Supplementary Note 3. More information on the experimental and finite element simulations set-ups on Methods: “Experimental Setup” and “Finite Element Simulations” respectively.
