Experimental Investigation of Band Gaps in Two-Layered Elastic Metamaterials with Arrays of Strip-Like Voids

Artificial periodic composite structures have great potential for the development of transducers, sensors, as well as smart systems and structures for active noise reduction, transducer design, energy harvesting, etc. In this paper, elastic metamaterials with multiple arrays of strip-like voids are proposed for providing wide band gaps, in which elastic waves cannot propagate. The goals of the present study are the manufacturing of these elastic metamaterials and the experimental investigation of wave propagation in such periodic structures. Several samples of elastic metamaterials have been manufactured on a dual extruder 3D printer since the dissimilar components do not demand additional bonding and have been fused by a heated extruder during printing. A laser Doppler vibrometer has been used to detect the wave motion, excited by a rectangular piezoelectric transducer. Wide band-gaps were observed in the measured transmission coefficient for the manufactured specimen.