Abstract：Elastic wave metamaterials are artificial periodic structures can control elastic waves. It can be used in aeronautics and astronautics, vehicle engineering and other fields. In this paper, a kind of tunable metamaterial with two magnetic resonators are proposed. The stainless steel plate is used to connect the magnetic resonator to the external frame in this structure. Adjusting the distance between the magnets can affect the in-plane stress of the stainless steel plate to affect the internal stiffness. By adjusting the cell structure, the double-cell system with different internal stiffness can be formed to achieve a wider coupling band gap. First, the trend of the stiffness of thin plate and the negative stiffness of magnetic force with distance between two magnetic resonators are obtained. The dispersion relationship and the transmissibility of the double magnetic resonators single cell metamaterial and two-cell metamaterial formed by adjusting the distance between magnets are obtained via theoretical model. Then, the effect of distance between two magnetic resonators on metamaterial bandgap and double-cell coupled bandgap in a specific case are further studied. Last, the experimental model was designed and manufactured by 3D printing technology. The transmissibility curves at different distance between two magnetic resonators were measured. The bandgap coupling results of double-cell metamaterial structures are verified. The theoretical prediction bandgap of the metamaterial agrees well with experimental results. This adjustment method can provide a new idea for the active control of restraining elastic wave transmission.
2024, Vol. 45 
