Study on sound absorption properties of closed cell aluminum foam with different microporous structures

Abstract

With the rapid development of modern society, environmental pollution is increasingly serious, among which noise pollution has become the world’s three major. At present, the methods to solve the noise problem are becoming more and more diverse. Among them, the use of porous materials for sound absorption and noise reduction is still one of the most important ways. Open-cell aluminum foam has high manufacturing costs and limited application scenarios. Therefore, some scholars have studied low-cost closed-cell aluminum foam, hoping to improve its sound absorption coefficient. Closed-cell aluminum foam is mainly used in sound insulation and has little sound absorption ability. For improving closed-cell aluminum foam sound absorption property, some scholars have researched the influence of mechanical perforation on the acoustic property of aluminum foam, but the sound absorption potential of small holes cannot be played due to the large aperture made during the process. Therefore, this paper designs and processes different aluminum foam sound absorption structures based on high-speed EDM technology and studies the effect of perforation aperture, perforation depth, and perforation rate on sound absorption peak value and sound absorption coefficient in low and middle-frequency bands (250HZ-2000Hz).