文章信息/Info

Title:

Acoustic performance of complex structure made by porous metal fibers materials 

作者:

王建忠; 湯慧萍*; 敖慶波; 馬軍; 李愛君

西北有色金屬研究院 金屬多孔材料國家重點實驗室

Author(s):

WANG Jianzhong;  TANG Huiping*;  AO Qingbo;  MA Jun;  LI Aijun

State Key Laboratory of Porous Metal Materials, Northwest Institute for Nonferrous Metal Research

關鍵詞:

多孔材料; 金屬纖維; 穿孔板; 復合結構; 吸聲; 隔聲

Keywords:

Porous materials;  Metal fiber;  Perforated panel;  Complex structure;  Sound absorption;  Sound insulation

DOI:

10.7502/j.issn.1674-3962.2017.07.08

文獻標志碼:

A

摘要:

針對精密電子元器件等領域受限空間內的噪聲處理難題，本文以纖維直徑為?8 ?m ~ ?20 ?m的316L不銹鋼纖維為原料，首先采用真空燒結技術制備了厚度為2 mm，孔隙率為55% ~ 76%的不銹鋼纖維多孔材料，然后將其與穿孔板、金屬薄板復合并采用真空燒結技術制備了厚度為3 ~ 4 mm的復合結構，利用4206型聲學阻抗管測試了金屬纖維多孔材料及其復合結構的吸聲系數和隔聲量。系統分析了不銹鋼纖維多孔材料的孔隙率與纖維直徑、穿孔板結構參數及金屬薄板對復合結構的吸聲性能和隔聲性能的影響規律。研究表明：當金屬纖維多孔材料的厚度為2 mm時，宜選擇單層復合結構進行噪聲處理，其吸聲系數穩定在0.3~0.4；當聲波頻率超過3000 Hz時，宜選擇梯度復合結構進行噪聲處理，其吸聲系數最高可達0.75。穿孔板顯著提高了復合結構的吸聲系數，且穿孔板的穿孔率對復合結構吸聲系數的影響遠大于其孔徑的影響。相對于穿孔板吸聲結構而言，復合結構將第一共振頻率向低頻方向移動且將共振頻率附近的吸聲頻帶變寬。在梯度金屬纖維多孔材料層間添加金屬薄板后，可進一步提高其吸聲系數。

Abstract:

In order to control the noise in the limited space in the field of precision electronic device, porous stainless steel fiber materials, which were the thickness of 2 mm and the porosities of 55% ~ 76%, were prepared by sintering process in the vacuum using the 316L stainless steel fiber with the diameters of 8?m to 20 ?m in the paper. Then the complex structure with the thickness of 3 ~ 4 mm was made using the porous stainless steel fiber materials, the perforated panel and the thin metal plate by sintering process in the vacuum. The sound absorption coefficient and the transmission loss of porous metal fiber materials and the complex structure were tested by the acoustic impedance tube with the type of 4206. The effects of the porosity and the fiber diameter of porous stainless steel fiber materials, the parameters of the perforated panel and the thin metal plate on the sound absorption and sound insulation properties were systematically analyzed. To control the noise, the single complex structure should be used and the sound absorption coefficient is stable about 0.3 to 0.4 when the thickness of porous metal fiber materials is 2 mm. Furthermore, the gradient complex structure should be used and the maximum sound absorption coefficient is about 0.75 when the sound frequency is higher than 3000 Hz. In addition, the sound absorption coefficient of complex structure can be obviously improved by adding the perforated panel in the front of porous metal fiber materials. The effect of punching rate of the perforated panel on the sound absorption coefficient of the complex structure is higher than that of the pore size of the perforated panel. The first resonance frequency of complex structure moves to the lower frequency direction and the sound absorption frequency range widens at the adjacent resonance frequency compared with the perforated panel. Additionally, the sound absorption coefficient of gradient porous metal fiber materials also can be improved by adding the thin metal plate at the interface between single porous metal fiber materials.