Abstract: In this paper, the relationship between sound absorption properties of porous metal-fiber material with inner cavity, and the kind of inner medium, depth and position of cavity is studied. The results show that as medium is air the average absorption coefficient of is 0.62 which is higher than 0.58, that of structure without cavity. But as the cavity filled with sulfate the average absorption coefficient goes down to 0.52. As the depth of cavity increased from 3.5 mm to 6mm, the average absorption coefficient also increased from 0.53 to 0.56 with absorbtion band broadening. The closer of the distance from cavity to absorption surface, the better properties of sound absorption are gained. For the inner structure with many dispersed cavities, the absorption properties of material may be further improved.

Key words: acoustics , metal fibber , porous sound absorption material , absorption coefficient

摘要： 研究具有空腔结构的金属纤维吸声材料的吸声性能与空腔内填充介质、空腔厚度以及位置之间的关系。实验结果表明，当空腔内填充介质是空气时，材料的平均吸声系数为0.62，高于无空腔结构的0.58；当空腔内填充致密的硫酸盐时，材料的平均吸声系数为0.52，吸声性能下降。当空腔的厚度分别为3.5 mm和6 mm时，平均吸声系数分别是0.53和0.56，吸声频带拓宽。当空腔结构相同时，空腔距离吸声表面越近，材料吸声性能越好。当内空腔为离散小空腔时，可有效提高平均吸声系数，拓宽吸声频带。

关键词: 声学 , 金属纤维, 多孔吸声材料, 吸声系数