Energy absorbing behaviour of additively manufactured auxetic composite lattices

Through the development of a novel cellular design tool, the geometry of each lattice and how this influences relative volume was studied.<br>Samples were additively manufactured using a short fibre composite 3D printing material and then experimentally tested under uni-axial tensile and compression testing, 3-point bending and low velocity impact. The results chapters focus on the testing and comparison of the cellular lattices under the previously mentioned testing methods.

Lattices with identical outer volumes were analysed to assess the influence of unit cell topology on the compressive, bending and tensile performance.<br>Finally, three hybrid auxetic lattices which combine alternate layers of hexagonal (non-auxetic) and re-entrant, double arrowhead or anti-tetra-chiral (auxetic) unit cells have been proposed and a preliminary computational study has been undertaken. A computational simulation was experimentally validated and revealed that the hexagonal-double arrowhead hybrid is capable of providing an increase in specific energy absorption over the conventional hexagonal lattice when both were loaded axially.