以1mm厚ⅡR薄片为基体,研究了其中炭黑、中空玻璃微珠、铝粉含量对材料吸声性能的影响情况。研究表明,1mm厚ⅡR薄片的第一吸声频带为3150-5000Hz,吸收峰频率为4000Hz,吸声效果以中空玻璃微珠最好,炭黑次之;当玻璃微珠/IIR=0.5时,材料出现第二个吸收频带2000-3000Hz,第二吸收峰频率为2500Hz,在频率为2500Hz处其最高吸声系数达0.15;当铝粉/IIR=(0.5-1.0)时,随着铝粉含量的增加,复合材料的第一吸收频带逐渐向低频移动。在玻璃微珠/ⅡR、铝粉/ⅡR材料中加入金属网,可以有效地强化复合材料的低频吸声效果。
Study on IIR slice of 1mm,We discuss the effect of carbon,aluminum particles,hollow glass bead on the property of sound absorption. It is found that the first sound frequency-band is 3150-5000Hz when sample' thickness is 1mm. The frequency of absorption peak is 4000Hz. omparing with carbon, the sound absorption of hollow glass bead effect is better. The material appears the second frequency-band between 2000-3000Hz and the absorption peak is 2500Hz when the ratio of hollow glass bead/ⅡR is 0.5. The maximum is 0.15 when frequency is 2500Hz. With the increase of aluminum particles the first frequency-band of composites moves towards low frequency when the ratio of aluminum particles/ⅡR is between 0.5 and 1.0. Adding wire netting in hollow glass bead/ⅡR and aluminum particles/ⅡR can strengthen sound absorption effect of low frequency of composites.