Elastic properties of 2D auxetic honeycomb structures- a review

The research field of auxetics, materials or structures exhibiting a negative Poisson's ratio, has received attention because of the unusually advantageous material properties that can be achieved with it, such as high indentation resistance and high shear resistance. In the past decades, the theoretical understanding of different factors that can lead to an auxetic behaviour has advanced greatly, resulting in a rapid increase in the number and type of the structures designed to exhibit this behaviour. These now exploit a number of different mechanisms, providing a large selection of properties which can be tailored for the specific needs. This review aims to describes the auxetic structures that have currently been identified and designed, describing the different approaches utilised to define their mechanical behaviour and analysing their structural properties, limitations, and potential field of application. In particular, the focus lies on the major works within the field, discussing their limitations and addressing works done to complement them.