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Materials Science in Additive Manufacturing TPMS for perfect sound absorption

Figure 3. Design model of graded primitive structures with different thicknesses
Abbreviation: GP: Graded primitive

Figure 4. Design model of multicavity-GP-Ⅰ and multicavity-GP-Ⅱ
Abbreviation: GP: Graded primitive

coefficients at 500, 630, 800, 1000, 1250, 1600, 2000, 2500, Table 4. The processing parameter for laser powder bed
3150, 4000, 5000, and 6300 Hz. fusion

2.4. Acoustic band structure Laser Scanning Layer thickness Scanning
power (W) speed (mm/s) (mm) space (mm)
The Bloch wave vector k of TPMS is applied to analyze the 200 1200 0.03 0.09
band gap of the acoustic metamaterial and is considered a
complex (Equation VII); k’ is the real component, and k” Table 5. Chemical composition of AlSi7Mg powder
is the imaginary component of the Bloch wave vector k.
The imaginary part represents the amplitude attenuation Element Al Si Mg Ti Fe Zn
characteristics of a wave. When k” = 0, it indicates that the Composition (wt. %) Balance 7.01 0.56 0.15 0.073 0.015
wave is a free-traveling wave, and the phase changes along
the wave propagation direction, whereas the amplitude curve of the imaginary part k” of the Bloch wave vectwith
remains unchanged. When k” ≠ 0, it indicates that the wave frequency, the bandgap range of the acoustic metamaterial
is attenuated. Therefore, by analyzing the changes in the can be determined.

Volume 4 Issue 1 (2025) 6 doi: 10.36922/msam.5737