低频条件下泡沫铜吸声性能的研究

The Research on Sound Absorption Performance of Copper Foam Under the Condition of Low Frequency

泡沫金属具有很好的高频吸声特性,在低频时吸声效果并不明显。采用驻波管法对泡沫铜进行低频下的吸声系数测试,实验结果表明,在低频下,泡沫铜的吸声系数很低。1800 Hz时,厚度10 mm的泡沫铜吸声系数只有0.125;当在泡沫金属厚加入空气层时,其吸声性能明显改善,1800Hz情况下,厚度10 mm的泡沫铜加10 mm厚空腔时,其吸声系数增加到0.3,空腔厚度20 mm时,其吸声系数增加到0.485.

Metal foam have good sound absorption properties under high frequency, while the effece is not obvious under low frequency. Standing wave method is used to test the sound absorption coefficient of copper foam under low frequency, the results show that the sound absorption coefficient of the copper foam is very low under the low frequency, the absorption coefficient of 10 mm copper foam is only 0.125 under 1800Hz. The sound absorption performance is obviously improved when join in a certain thickness of air layer, with a cavity of 10 ram, the sound absorption coefficient increases to 0.3 of 10 mm copper foam and increases to 0.485 of 20 mm copper foam.