3D Printed Structures for Ultrasound Attenuation in Underwater Environment

Area of Science:

• Materials Science
• Acoustics
• Additive Manufacturing

Background:

• Ultrasonic wave attenuation is crucial for underwater applications.
• Designing materials with tunable acoustic properties remains a challenge.
• 3D printing offers precise control over complex structures.

Purpose of the Study:

• To investigate the ultrasonic wave attenuation capabilities of 3D printed structures with air cavities.
• To identify key structural and material factors influencing attenuation performance.
• To demonstrate the potential of additive manufacturing for designing optimized acoustic metamaterials.

Main Methods:

• Open or closed air cavity structures were fabricated using direct ink writing (DIW) with polydimethylsiloxane (PDMS) and fused deposition modeling (FDM) with thermoplastic polyurethane (TPU).
• The ultrasonic attenuation capacity of these 3D printed structures in an underwater environment was systematically examined.
• Factors including interstitial fencing, air cavity fraction, material interfaces, and material properties were analyzed.

Main Results:

• Attenuation performance is governed by interstitial fencing, air cavity fraction, material interface interactions, and material properties.
• 3D printing allows for convenient manipulation of cavity volume fraction (e.g., filament size, surface density) to achieve tunable attenuation.
• Geometric designs that increase interface interactions, such as triangular shapes, significantly enhance ultrasonic attenuation.

Conclusions:

• 3D printing techniques enable the design of structures with tunable ultrasonic attenuation properties.
• Optimizing acoustic metamaterials can be achieved by controlling air cavity fractions and employing interface engineering.
• Convoluted structural interface design, exclusively tailored by additive manufacturing, offers a novel approach for substantial attenuation enhancement.