ACOUSTIC PERFORMANCES OF METAL SAMPLES MANUFACTURED BY ADDITIVE TECHNOLOGIES

Abstract

Porous materials (PMs) have been widely used since the development of powder metallurgy. PM samples are obtained by\nvarious methods, while the structure varies from sample to sample. Deviation from a given structure leads to a deviation of the specified\nproperties up to 30%, including acoustic. Selective laser melting (SLM), allows to obtain samples with a low structural deviation\n(up to 13%) in a wide porosity range P=0.3-0.7. An increase in the sound absorption coefficient and the expansion of the frequency\nrange allows to use such samples in noise reduction units’ designs.\nNine samples with different porosity and cell shape were obtained by the SLM method with the use of AlSi10Mg aluminum powder obtained\nby gas atomization and BB751P nickel powder obtained by plasma centrifugal spraying. The porosity of the samples (P) varied\nin the range (0.3–0.7), the diameter was D = 34.5 mm, and the height varied in the range of 15–45 mm.\nThe acoustic characteristics comparison of traditional PMs with porous fused material (PFM) by the sound absorption index shows\nthat PM, as a rule, are superior to PFM, while it is approximately equal to porous cast