Fabricating and Assembling Acoustic Metamaterials and Phononic Crystals

• Published in: Advanced engineering materials 2021-02, Vol.23 (2), p.n/a
• Main Authors: Choi, Christabel, Bansal, Shubhi, Münzenrieder, Niko, Subramanian, Sriram
• Format: Article
• Language: English
• Subjects: acoustic metamaterials; fabrication methods; microfabrication; phononic crystals
• ISSN: 1438-1656; 1527-2648
• DOI: 10.1002/adem.202000988

Acoustic metamaterials (AMM) and phononic crystals (PC) have the potential to unfold a new wave of disruptive technologies to radically transform human interactions, sensory communications, and beyond. Although essential, cultivating a deep understanding of the fundamental theory and design principles is insufficient alone, in the practical advancement of AMMs and PCs. Equally important is the physical realization of these artificial structures for tangible prototyping and experimental investigation; however, such aspects are seldom discussed in literature. Herein, the fabrication and assembly approaches for AMMs and PCs are critically examined, with a tight coupling of theoretical and experimental considerations. Crucial parameters like operating frequency, materials, and geometry for efficient structural implementation are addressed. Herein, fabrication methods for specific structure types are categorized under “single‐step fabrication” including printing and machining and “multi‐step fabrication” like microfabrication and molding. Various “assembly” techniques are proposed, such as for ordering colloidal assemblies or fastening components without adhesives. This framework uncovers innovative designs, e.g., origami‐based structures with conductive coating, only accessible if fabrication and assembly aspects form an integral part of the initial design phase. By establishing a greater understanding and awareness of these methods, a host of undiscovered pathways, opportunities, and research gaps is revealed, supporting a fresh paradigm for innovation. Promoting the physical realization of acoustic metamaterials (AMMs) and phononic crystals (PCs) is an essential step toward motivating the practical and industrial advancement of novel acoustic structures. Based on representative AMM and PC structure types, the techniques to build them are discussed within the strategic categorization of relevant fabrication and assembly methods. This framework guides toward inspiring new acoustic designs.