All-in-One Underwater Quality Evaluation Metamaterial With Mechanical Robustness, Sound Attenuation, and Diffuse...

Area of Science:

• Materials Science
• Acoustics
• Biomimetics

Background:

• Underwater acoustic coatings face challenges in balancing acoustic-mechanical properties under pressure.
• Existing solutions often lack broad low-frequency sound attenuation or robustness against hydrostatic pressure.

Purpose of the Study:

• To design and validate a novel underwater composite structure for enhanced low-frequency sound attenuation.
• To address acoustic-mechanical conflicts and research gaps in underwater acoustic materials.
• To develop a bio-inspired approach for robust underwater acoustic skins.

Main Methods:

• Biomechanical inspiration from jumping spiders and human bones to design a composite structure.
• Theoretical modeling, numerical simulation, and experimental validation.
• Integration of acoustic-electrical analogy and convolutional neural networks for design and evaluation.

Main Results:

• Achieved low-intensity diffuse reflection below 0.8 kHz and broadband low-frequency sound attenuation (insulation > 26 dB, absorption > 0.8) from 0.8-2.5 kHz.
• Demonstrated significant sound attenuation (absorption > 0.8) below 4 kHz even under 3 MPa hydrostatic pressure.
• Showcased high pressure resilience with minimal performance decrease (4.5% per 1 MPa) and near-complete deformation recovery.

Conclusions:

• The developed bio-inspired composite structure offers effective and robust low-frequency sound attenuation for underwater applications.
• The integrated design-evaluation framework provides a scalable approach for next-generation underwater acoustic skins.
• This work bridges the gap between acoustic performance, mechanical robustness, and bio-inspired design for marine technologies.