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Stretchable materials that can sustain a large deformation are in high demand, because they find broad applications ranging from stretchable energy storage devices to tunable noise and vibration devices. One main challenge is creating strain‐releasing mechanisms from inherently brittle materials. This work explores a new approach to designing stretchable metamaterials, using a kerfing pattern inspired by the ancient Greek Key configuration. The kerfing architecture allows for substantial in‐plane elongation. In‐plane tensile experiments show an ≈8‐times increase in stretchability when the kerfing width is enlarged four times. With higher‐order fractal patterns, the fractal lattice exhibits a stretchability of up to ≈520%, far beyond the inherent deformability of the brittle constituent. Moreover, this design also enables the tunability of various mechanical properties, including stiffness, strength, toughness, and Poisson's ratio. Ashby‐type plots are presented, revealing the relationships between stretchability and other mechanical properties to aid in the design and fabrication of advanced engineering materials. To demonstrate a vital application of the achieved stretchability, elastic wave propagation in the proposed kerfing metamaterials is studied. Simulations indicate that multiple broad phononic bandgaps arise in these structures as the fractal order increases. These bandgaps prove to be adjustable not only through the fractal lattice geometry but also by means of applied mechanical loading. This investigation highlights the potential of fractal‐based layouts as a promising avenue for designing cutting‐edge stretchable metamaterials with customizable mechanical properties and functionalities.
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Opportunities for Nanomaterials in Stretchable and Free‐Form Displays
Stretchable and free‐form displays receive significant attention as they hold immense potential for revolutionizing future display technologies. These displays are designed to conform to irregular surfaces and endure mechanical strains, making them well suited for applications in wearable electronics, biomedical devices, and interactive displays. Traditional light‐emitting devices typically employ brittle inorganic and metallic materials, which are not conducive to stretchability. However, replacing these nonflexible components with flexible/stretchable nanomaterials, soft organic materials, or their composites improves the overall flexibility and stretchability of devices. In this review, the roles and opportunities of nanomaterials, such as thin films, 1D nanofibrous materials, and micro/nanoparticles, are highlighted for enhancing the stretchability and overall performance of various types of light‐emitting devices. By leveraging the unique mechanical and electrical properties of nanomaterials, various efforts emerge to push the boundaries of stretchable display technologies and further realize their full potential for diverse applications.
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- PAR ID:
- 10492899
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Small Science
- ISSN:
- 2688-4046
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1002/smsc.202300143
