Solid buoyancy materials are also widely used in the military. At present, the main body of integrated buoy for domestic submarine is made of solid buoyancy material with high strength and low density.
An integrated buoy is a special device released by a submarine and connected to it by a towed cable. When the submarine pulls the buoy forward, the buoy travels close to the surface of the sea by its hydrodynamic characteristics. The buoy is composed of a main floating body and a stabilizing device. The integrated buoy can make up for the weak point of submarine's poor communication ability to a large extent. The short wave and ultra-short wave of the integrated buoy can ensure the smooth communication with the shore and sea fingers, and open up new combat styles such as the cooperation of various arms. Towed buoy can not only solve the bottleneck problem of submarine communication for a long time, but also improve the underwater submarine observation and warning ability, as well as implement the communication with sea commanders and other forces, and improve the submarine cooperative combat ability. The terminal and monitoring equipment of the corresponding equipment on the buoy are installed on the submarine to realize data exchange, processing and remote control. Since 2000, the Research Institute of Ocean Chemical Industry has produced multiple sets of integrated buoys for submarine, and in the long-term use process, the performance of the material is stable and the working condition is good.（From 《Solid Buoyant Materials》）