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采用加压铸造工艺成功地制备了多孔铝合金，孔隙尺寸为０．５～１．６ｍｍ，孔隙率为６０％～８０％，通孔率为８５％～１００％，最大制品尺寸为ｄ１００ｍｍ×１００ｍｍ。扫描电镜观察表明，在焙烧期间预制块颗粒形状由尖角形变为圆形，颗粒之间的搭接面积变大且过渡平缓；所得多孔金属孔隙形状圆滑，互相连通，呈三维网状结构。对多孔金属进行的吸声性能测试表明，多孔金属具有较大的吸声系数，不同的多孔铝合金其吸声系数随频率的变化趋势基本相同，当声波频率增加时，多孔铝合金的吸声系数增大。另外降低多孔铝合金的孔隙尺寸和增加其孔隙率，均会使多孔铝合金的吸声系数增大。在实验测试频率范围内，当声波频率在３．５ｋＨｚ时，多孔铝合金的吸声系数达到最大
Porous aluminum alloy was successfully prepared by pressure casting process, the pore size is 0.5 ~ 1.6mm, the porosity is 60% ~ 80%, the via rate is 85% ~ 100%, the largest product size is d100mm × 100mm . Scanning electron microscopy showed that during the calcination, the shape of the preform particles changed from a sharp corner to a circular shape, the overlapping area between the particles became larger and the transition was gentle. The porous metal obtained was smooth and interconnected with a three-dimensional network structure. The sound absorption performance test of porous metal shows that the porous metal has a large sound absorption coefficient. The sound absorption coefficient of different porous aluminum alloys changes basically in the same frequency. When the sound frequency increases, the sound absorption of the porous aluminum alloy The coefficient increases. In addition, reducing the pore size of the porous aluminum alloy and increasing the porosity thereof will increase the sound absorption coefficient of the porous aluminum alloy. In the experimental test frequency range, when the sound frequency at 3.5kHz, the porous aluminum alloy to achieve the maximum absorption coefficient