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Updated: Jun 18, 2025
09:39
Characterizing Dissipative Elastic Metamaterials Produced by Additive Manufacturing
Published on: June 28, 2024
890
Guiding near-source elastic waves in a semi-infinite medium.
Kemeng Cui1, Zhao-Dong Xu1, Antonio Palermo2
1China-Pakistan Belt and Road Joint Laboratory on Smart Disaster Prevention of Major Infrastructures, School of Civil Engineering, Southeast University , Nanjing 211189, People's Republic of China.
Summary
Researchers developed elastic metamaterials that steer bulk waves using phase discontinuities. This innovation enables precise control over wave propagation for applications like vibration isolation and energy harvesting.
Area of Science:
- Solid mechanics
- Materials science
- Acoustics
Background:
- Elastic metamaterials offer unique wave manipulation capabilities.
- Controlling bulk wave propagation in semi-infinite media presents significant challenges.
Purpose of the Study:
- To propose and demonstrate elastic metamaterials with phase discontinuities for steering near-source bulk waves.
- To achieve wavefront manipulation for directional refraction and energy focusing.
Main Methods:
- Design of subwavelength resonators with tailored masses to achieve a complete phase shift.
- Utilizing dispersion diagrams and the generalized Snell's law.
- Employing a multiple scattering formulation for analytical demonstration.
Main Results:
- Successful demonstration of wavefront manipulation through tailored phase discontinuities.
- Achieved diverse wave functionalities including directional refraction and energy focusing.
- Validated the effectiveness of the proposed metamaterial design.
Conclusions:
- The proposed elastic metamaterials effectively steer bulk wave propagation.
- This design offers potential advancements in guiding elastic waves.
- Applications include ground-borne vibration isolation and energy harvesting.
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