摘要 |
A thermoformable acoustic sheet material that is lightweight and provides excellent sound attenuation over a wide range of frequencies includes a combination of sound attenuating materials, including an acoustic barrier having a relatively high density, a thermoformable sound absorbing layer having a relatively low density, a substantially air-impermeable layer between the barrier and the sound absorbing layer, and an acoustic performance enhancing scrim or perforated thermoplastic film on the opposite side of the sound absorbing layer. The combination is useful for preparing contoured acoustic treatments for reducing sound transmission from the engine compartment of a vehicle to the passenger compartment of the vehicle.
|