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A Lightweight and Transparent Composite-Perforated Janus Acoustic Metamaterial: Multi-Band Sound Absorption Realized
Xinxin Liu1,2, Guangjun Zhang1,2, Jingbo Zhao1,2
1Shaanxi Key Laboratory of Artificially Structured Functional Materials and Devices, Air Force Engineering University, Xi'an 710051, China.
Materials (Basel, Switzerland)
|August 13, 2026
Summary
This study introduces a transparent Janus acoustic metamaterial that overcomes limitations of traditional sound absorbers. The novel material offers tunable, dual-frequency sound absorption, ideal for light-permitting applications.
Area of Science:
- Acoustics
- Materials Science
- Metamaterials
Background:
- Conventional sound-absorbing structures suffer from fixed frequency bands, single functionality, and limitations in light-limited spaces.
- There is a need for advanced acoustic materials that offer tunable absorption and multifunctionality.
Purpose of the Study:
- To design and fabricate a composite-perforated Janus acoustic metamaterial using transparent SLA resin.
- To investigate the sound absorption mechanisms and the effects of geometric parameters on performance under different incidence conditions.
Main Methods:
- Acoustic impedance theory
- Parametric finite-element simulations
- Impedance-tube experiments
- Fabrication using transparent SLA resin
Main Results:
- Achieved near-unity low-frequency narrowband absorption (322 Hz) under forward incidence.
- Observed a shifted absorption peak (658 Hz) with a broader effective band under reverse micro-perforated incidence.
- Demonstrated independent tuning of absorption bands via bilateral geometric decoupling.
Conclusions:
- The Janus acoustic metamaterial overcomes limitations of narrowband performance and functional singularity.
- Optical transparency and tunable dual-band absorption offer novel noise control for specific applications.
- Provides a reference for designing multifunctional asymmetric acoustic metamaterials.
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