Designing nonwoven auxetic metamaterials with spatially textured functionalities

Abstract Mechanical metamaterials are an extraordinary class of materials that harness their unusual characteristics from the geometrical features. Herein, we report a design strategy to decipher anisotropic and aperiodic nonwovens as auxetic metamaterials by carefully decorating with the slit perforations in a stochastic manner. These slit perforated nonwoven materials have been tested under uniaxial tensile deformation by altering the aspect ratio of the specimen dimensions. Ostensibly, the slit perforations in nonwovens created the invariant behavior towards the test direction and the aspect ratio of the specimen dimensions. These slit perforations have led to the geometrical frustration-free structures that are of paramount importance to avoid any hindrance to the desired functionality.