Trapping and attenuating broadband vibroacoustic energy with hyperdamping metamaterials

We introduce a class of engineered metamaterials for the purpose of attenuating and trapping spectrally broadband vibration and acoustic energy. The physical phenomenon realized to effect such wideband energy dissipation performance is termed hyperdamping since it is the consequence of eliminating fundamental stiffness contributions within the material system so as to asymptotically enhance damping properties. A strategically sculpted elastomer topology is geometrically constrained and embedded in a poroelastic matrix to realize the metamaterial platform. Finite element model analyses guide design of the embedded hyperdamping inclusions while experimental studies on dynamic force transmissibility and acoustical absorption coefficient provide conclusive evidence that hyperdamping phenomena facilitate wideband energy dissipation in a lightweight material system that is not subject to the limitations of conventional resonance- or bandgap-based attenuation effects. The hyperdamping metamaterials thus meet the often conflicting performance requirements of real applications where broadband vibrations and noise must be abated using lightweight material solutions.