The difference between soundproof materials and sound-absorbing materials

The difference in material between these two materials is:

The reflection of incident sound energy by sound-absorbing materials is very small, which means that sound energy can easily enter and pass through this material; The material of this material should be porous, porous, and breathable, which is a typical porous sound-absorbing material. In the process, fibrous, granular, or foaming materials are usually used to form a porous structure; The structural feature is that the material has a large number of interconnected micropores from the surface to the inside, which means it has a certain degree of breathability. When sound waves are incident on the surface of porous materials, they cause air vibration in the micropores. Due to frictional resistance, air viscosity resistance, and thermal conduction, a considerable amount of sound energy is converted into heat energy, thereby playing a role in sound absorption.

Sound insulation materials can weaken the transmission of sound energy and block the propagation of sound. They cannot be porous, loose, or breathable like sound-absorbing materials. On the contrary, their materials should be heavy and dense, such as steel plates, lead plates, brick walls, and other materials. The material requirements for sound insulation materials are dense without pores or gaps; Has a significant weight. Due to the compactness of such sound insulation materials, it is difficult to absorb and transmit sound energy while reflecting strong energy, resulting in poor sound absorption performance.