AUXHEX – a Kirigami inspired zero Poisson's ratio cellular structure

This work describes the development, manufacturing and testing of a zero Poisson’s ratio PEEK cellular structure (AuxHex) made using Kirigami-inspired techniques. The AuxHex hybrid cell pattern is a combination of cells with different shapes that interlock with each other. This principle can lead to graded honeycombs possessing, in different areas, synclastic as well as anticlastic behavior. The AuxHex samples produced have been tested for flatwise compression according to ASTM standards and the results are compared with a unit-cell-based analytical model. Hexagonal-cell shaped honeycombs were also produced with the same technique and used for direct comparison. The mechanical flatwise properties have been benchmarked against the ones of other experimental PEEK-based cores and commercially available honeycombs. AuxHex samples are found to have higher stiffness compared to other experimental PEEK honeycombs, but lower compared with the commercially available honeycombs. The strength thought, while it is still higher compared to the other experimental PEEK cores, it is comparable with other honeycomb configurations.