Auxetic materials have a negative Poisson’s ratio; they get thinner when compressed and thicker when stretched, which can lead to improved mechanical properties such as increased energy absorption and resistance to indentation. A potential application of these materials is protective sport equipment, where impact forces, and hence the risk of injury, can be reduced. Existing work shows this potential but involves time-consuming development and experimental testing of material samples. The aim of this research is, therefore, to apply a systematic finite element modelling method (an engineering technique that predicts the behaviour of materials and products under certain conditions) to better implement auxetics within sports equipment. The need for prototype development is thus reduced, resulting in a more efficient design process. Candidate auxetic structures were identified and subjected to quasi-static and impact simulations. These auxetic structures were made by additive manufacturing and then subjected to equivalent mechanical testing to validate the models.
The structure demonstrating the most favourable properties will be identified as the candidate auxetic for further investigation. This validated model can lead to the optimisation of cell parameters (e.g. angle, thickness) within the candidate auxetic and the regularisation of the structure to an appropriate scale for sports equipment application.