ACOUSTIC ABSORPTION CHARACTERISTICS OF FOAMED ALUMINUM

The acoustic absorption characteristics of foamed aluminum and the eff ect of its structural parameters on the characteristics have been inve stigated. The results indicate that the acoustic absorption behavior o f foamed aluminum has an uncertain relation with its porosity; the eff ect of pore size is non-monotonous, while the flow resistance, which c haracterizes the structural coefficients, might be the most important factor. It is also found that the absorption peak is widened and the n oise reduction coefficient can be increased through suitable compressi ve deformation.