The acoustic properties of syntactic foams can be tailored to yield interesting underwater acoustic characteristics. These materials are used in transducer isolators, acoustic windows, anechoic test tank liners, and subsea damping structures. Each application is unique and is dependent on the transparency, absorption, reflection, and refraction of the material. Since the acoustic impedance of syntactic foam is very close to that of water, acoustic waves are transmitted through the material without loss at the syntactic-water boundary.
Typical acoustic properties over a range of densities:
For some ESS customers the manner in which sound travels through syntactic materials is of considerable interest. It’s especially intriguing in the subsea environment because there is little change in acoustic properties at depth, allowing designers to match or decouple impedance properties to the surrounding environment.