Numerical optimization of a prestressed auxetic metamaterial for vibration isolation

Abstract: We present a numerical study on an enhanced periodic auxetic metamaterial. Rotating squares mechanism allied to precompression induced buckling give these elastic structures exotic properties. The static properties of the reference structure and the enhanced ones are first compared. After numerical analysis to ascertain the differences between several band calculation methods, we demonstrate the effect of precompression issued stress field on the dispersion diagram of the metamaterial. An optimization study is then performed to assess the potential vibration isolation improvement obtained with the new design. As a result, the bandgaps widths and range are found to be greatly increased by the geometric modifications proposed.