Page 31 - MSAM-4-1

Materials Science in Additive Manufacturing TPMS for perfect sound absorption

Table 1. Design parameters of uniform triply periodic minimal surface (TPMS) structures
Specimen Size of unit cell (mm) Thickness of porous structure (mm) Offset thickness of surface (mm) Porosity (%)
Gyroid-6 mm 3 6 0.265 75
Gyroid-12 mm 3 12 0.265 75
Gyroid-18 mm 3 18 0.265 75
Gyroid-24 mm 3 24 0.265 75
Gyroid-30 mm 3 30 0.265 75
Primitive-6 mm 3 6 0.3 75
Primitive-12 mm 3 12 0.3 75
Primitive-18 mm 3 18 0.3 75
Primitive-24 mm 3 24 0.3 75
Primitive-30 mm 3 30 0.3 75
IWP-6 mm 3 6 0.3 75
IWP-12 mm 3 12 0.3 75
IWP-18 mm 3 18 0.3 75
IWP-24 mm 3 24 0.3 75
IWP-30 mm 3 30 0.3 75
Diamond-6 mm 3 6 0.208 75
Diamond-12 mm 3 12 0.208 75
Diamond-18 mm 3 18 0.208 75
Diamond-24 mm 3 24 0.208 75
Diamond-30 mm 3 30 0.208 75
Abbreviation: IWP: I-Wrapped Package.

Table 2. Design parameters of multicavity triply periodic
minimal surface (TPMS) structures
Specimen Size of unit Constituent part
cell (mm)
Multicavity-gyroid 3 Gyroid-12 mm+Gyroid-18 mm
+Gyroid-24 mm+Gyroid-30 mm
Multicavity-primitive 3 Primitive-12 mm+Primitive-
18 mm+Primitive-24 mm
+Primitive-30 mm
Multicavity-IWP 3 IWP-12 mm+IWP-18 mm
+IWP-24 mm+IWP-30 mm
Multicavity-diamond 3 Diamond-12 mm+Diamond- Figure 1. Design models of uniform triply periodic minimal surface
18 mm+Diamond-24 mm (TPMS) structures
+Diamond-30 mm Abbreviation: IWP: I-Wrapped Package
Abbreviation: IWP: I-Wrapped Package.
and the manufacturing parameters are listed in Table 4.
including GP-12 mm-Ⅱ, GP-18 mm-Ⅱ, GP-24 mm-Ⅱ, and AlSi7Mg powder was applied to LPBF, and its particle
GP-30 mm-Ⅱ. The design parameters and design model size distribution is: D10 = 19.2 μm; D50 = 34.6 μm; and
of multicavity-GP-Ⅰ and multicavity-GP-Ⅱ structures are D90 = 60.8 μm. The chemical composition of AlSi7Mg
displayed in Table 3 and Figure 4. The porosity of GP and powder is listed in Table 5. TPMS specimens manufactured
multicavity GP structures was fixed at 75%. by LPBF are displayed in Figure 5.

2.2. LPBF preparation procedure 2.3. Sound absorption coefficient test
The acoustic metamaterials were manufactured using According to the ASTM E1050-12 standard, the absorption
LPBF equipment (Dimetal-280; Laseradd Co., Ltd., China), coefficient of acoustic metamaterial was measured using

Volume 4 Issue 1 (2025) 4 doi: 10.36922/msam.5737