Sound Absorption Characteristics of FeCrAl Sintering Fibrous Porous Materials

Abstract:

FeCrAl fibrous porous materials with the porosity larger than 85% were prepared using the fiber of 20 μm in diameter as starting material. Under the ordinary sound pressure and high sound intensity conditions, the sound absorption properties of FeCrAl sintering fibrous porous materials were tested. The results indicate that the sound absorption properties of FeCrAl fibrous porous materials were increased by increasing of the porosity under ordinary sound pressure. But it was not beneficial to sound absorption under high frequency when the porosity was too high or too low. The larger the thickness was, the better the sound absorption properties of FeCrAl fibrous porous materials were. Adding the airspace can improve the sound absorption properties under low frequency. Under high sound intensity (100-140 dB), the sound absorption properties of the material would not change with the sound pressure level (SPL); effects of the parameters on the sound absorption properties were in concordance with that under ordinary sound pressure. The sound absorption coefficient of FeCrAl fibrous porous materials with 94% porosity and 20 mm thickness was up to 90% at 120 dB and in the frequency range of 2.5-6.4 kHz.