We investigate two-dimensional phononic metaplates consisting of a periodic array of cups on a thin epoxy plate that is perforated with periodic cross holes. The cups are individually filled with water or remain empty, in view of creating reconfigurable phononic waveguides. Phononic band gaps exist for empty or filled epoxy cups, leading to waveguides defined with either positive or negative contrast. Straight and 90° bent waveguides are considered experimentally. Lamb waves are excited by a piezoelectric patch glued onto the metaplate and are imaged using a scanning laser vibrometer. Experimental results are compared to a three-dimensional finite element model of fluid–structure interaction. Passing and forbidden frequency ranges are identified for positive and negative contrast, and confined propagation is observed along the waveguides. Significantly, the propagation of acoustoelastic waves in the 90° bent waveguides is observed experimentally. Reconfigurability and reusability are thus realized based on the coupling of elastic waves in the solid and acoustic waves in the fluid. The results show plenty of potentiality for the practical design of multiplexed and programmable acoustic devices implemented with reconfigurable waveguides printed on demand in a phononic metaplate.

我们研究了二维声子金属板，该金属板由在带有周期性交叉孔的薄环氧树脂板上周期性排列的杯组成。考虑到创建可重新配置的声子波导，杯子单独装满水或保持空。空的或填充的环氧树脂杯存在声子带隙，导致波导定义为正对比度或负对比度。直波导和 90° 弯曲波导在实验中被考虑。兰姆波由粘贴在金属板上的压电贴片激发，并使用扫描激光测振仪成像。实验结果与流固耦合的三维有限元模型进行了比较。通过和禁止的频率范围被识别为正反差，并且沿着波导观察到受限传播。值得注意的是，声弹性波在 90° 弯曲波导中的传播是通过实验观察到的。因此，基于固体中的弹性波和流体中的声波的耦合，实现了可重构性和可重用性。结果表明，在声子金属板上按需印刷的可重构波导实现的多路复用和可编程声学设备的实际设计具有很大的潜力。