Study on sound insulation performance of Al foam sandwich board

Sound insulation performance of Al foam bare board and sandwich board was tested, the effect of density and thickness on acoustical behavior of Al foam sandwich board was studied. The results showed that, sound reduction index of Al foam sandwich board increased with the increase of sound wave frequency, sound reduction index during difference frequency was controlled by difference mechanism, it could be divided into three regions: rigidity and damp control region, quality control region and mixing influence region. With the increase of density and thickness of Al foam sandwich board, the sound insulation performance enhanced gradually, sound reduction index increased with the increase of sound wave frequency. At the condition that density and thickness were low, sound reduction index of Al foam sandwich board was better than that of Al foam bare board.