The comprehensive noise reduction coefficient of the new aluminum foam material reaches 0.75, and the sound absorption coefficient in the mid-frequency range of 250~1000Hz reaches more than 0.9, far exceeding the commonly used sound-absorbing materials such as rock wool, gypsum board, perforated metal plate, etc. Its comprehensive sound insulation and noise reduction ability is polyurethane foam. It is 7-10 times that of plastic, glass fiber and honeycomb aluminum, and its sound insulation is close to 30dB when used in high-speed trains and automobile box panels. The new aluminum foam material is used in more and more fields for its superior sound absorption and noise reduction and related properties, mainly in highway sound barriers, highway tunnel noise reduction, submarine tunnel noise reduction, tunnel vents; sound absorption of swimming pools wall; new foam aluminum material to make building sound-absorbing lining, such as recording studios, dubbing rooms, concert halls, conference halls, stadiums, etc.
The main factors affecting the sound absorption and noise reduction effect of new foam aluminum materials are as follows:
1. The new aluminum foam material is a porous material, and its sound absorption performance is more obvious for high frequency sound, that is to say, the sound absorption coefficient is large in the high frequency region. However, the sound absorption effect of low frequency sound is not very ideal, so the sound absorption coefficient in the low frequency region is small;
2. The thickness of the sound-absorbing board made of the new foam aluminum material is different, and the sound-absorbing frequency is different. With the increase of the thickness, the excellent frequency of sound-absorbing will develop towards the low-frequency absorption. However, when the frequency of the sound is greater than 500Hz, the sound absorption coefficient of the new foam aluminum material has nothing to do with the thickness;
3. When the density of the new aluminum foam material increases, the excellent sound absorption frequency at this time will also develop to low-frequency sound, and the pore size and number of the new aluminum foam material also have obvious differences in the sound absorption performance of the sound-absorbing panel.
To put it simply, different choices of new aluminum foam materials, such as thickness, density, porosity, etc., will result in different sound absorption effects. No matter how new aluminum foam materials are selected, it is more effective to fit their own situation.
