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探讨网状泡沫镍及其复合设计结构在声波低频区200～2000 Hz范围内的吸声性能。结果发现,对于孔隙率为89%,厚度为2.3 mm,平均孔径为0.57 mm的泡沫镍,1～5层泡沫体的吸声效果都很差。加入背后空腔和前置穿孔薄板都可提高吸声系数:5层叠加再加入5 mm厚的背腔,泡沫体的最大吸声系数在1000～1600 Hz内达到0.4左右;双层泡沫镍加入5 mm厚的背腔后,同时再在前面贴合一层穿孔薄板,泡沫体的吸声系数在1000 Hz左右时甚至达到了0.68。
In this paper, the sound absorption performance of reticulated nickel foam and its composite design structure in the range of 200-2000 Hz in the low frequency region of sound waves was discussed. The results showed that for foam nickel with a porosity of 89%, a thickness of 2.3 mm and an average pore diameter of 0.57 mm, the sound absorption effects of the layers 1 to 5 foam are poor. Addition of back cavities and pre-perforated sheets can increase the sound absorption coefficient: the 5-layer superposition adds a 5-mm-thick back cavity, and the maximum sound absorption coefficient of the foam reaches about 0.4 at 1000-1600 Hz. After a 5 mm thick back chamber, a thin layer of perforated sheet was attached to the front and the foam even reached a sound absorption coefficient of about 0.68 at about 1000 Hz.