Abstract:Sound absorption coefficient of closed-cell aluminum foam with different perforation size and arrangement was measured by standing-wave method. Sound absorption capacity was evaluated by the maximum sound absorption coefficient, noise reduction coefficient and half-peak width. The results show that specimens with perforation arranged in square way exhibit better sound absorption effect than those with perforation arranged in trigonal way. Sound absorption coefficient remains fundamentally unchanged as perforation size changes. The maximum sound absorption coefficient transfers to low frequency with increase of perforation size and noise ?reduction coefficient rises with increase of perforation rate. The half-peak width of specimens with perforation size of 1.5 mm and 2.5 mm is higher than those of 3 mm and 3.5 mm.