Coefficient of Sound Absorption of Polyamide PA12 Samples Manufactured by Selective Laser Sintering

Abstract

© 2021, Springer Nature Switzerland AG. Selective laser sintering is the additive manufacturing technology that is predominantly used for production of small series of products and prototypes, and the polyamide PA 12 represents the basic material for the technology process. The technology presents a reasonable choice for production of scientific instruments and laboratory equipment, as it is the case with the equipment for material characterization by sound absorption or emission. As the sound absorption by the instruments and equipment may affect interpretation of the obtained results, it is useful to know the frequency dependence of the sound absorption coefficient of the material used for their construction. The paper presents the results of measurements of the sound absorption coefficients of the PA12 samples with thicknesses between 0.7 mm and 2.2 mm in the frequency range between 125 Hz and 2.5 kHz, which is predominantly used in the photoacoustic applications. The measurements were performed according to the method SRPS ISO 9053, using the resistance of the airflow measurements and the Miki model. The obtained results show that the sound absorption coefficient of the PA12 samples manufactured by laser sintering are lower than 0.05 within the frequency range, and that it monotonously increases with frequency, similar to the behaviour of some other studied polymers and composite materials based on polymers.