Surface wettability induced variation of underwater acoustic transmission coefficient of the membrane resonators

Abstract

The capability to effectively manipulate the transmission coefficient is essential to the detection sensitivity of underwater acoustic equipment. Here we present a tunable transmission coefficient of the underwater membrane resonators by adjusting the surface wettability of the copper platelets. The variation of the surface wettability of the copper platelet can be realized by laser texturing and chemical modification, which further induces an alternative adhesive force. When the membrane resonators are penetrated by an acoustic wave underwater, it exhibits modified vibration patterns attributed to the different surface adhesive force of the attached copper platelet. A greater adhesive force of the copper surface leads to a higher transmission coefficient of the membrane resonators. The transmission coefficient can be adjusted in a range of [−12%, 8%] in comparison to the pristine copper surface in accordance to an adhesive force. This work shows excellent potential in underwater sonic sensing and communication.