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Tunable wrinkling pattern in annular graphene under circular shearing at inner edge
1Department of Civil and Environmental Engineering, National University of Singapore, Kent Ridge, Singapore 119260. ceezzhen@nus.edu.sg
Nanoscale
|July 11, 2012
Summary
Circular shearing of annular graphene sheets causes unique, confined wrinkling patterns. The wave number depends on the inner radius, while wrinkle profiles are affected by shear magnitude, enabling potential nano-device applications.
Area of Science:
- Materials Science
- Nanotechnology
- Solid Mechanics
Background:
- Graphene sheets exhibit complex mechanical behaviors under stress.
- Wrinkling is a common phenomenon in thin materials, but patterns vary with geometry and loading conditions.
Purpose of the Study:
- To investigate the wrinkling phenomenon in annular graphene sheets subjected to circular shearing.
- To characterize the resulting wrinkle patterns and their dependence on geometric and loading parameters.
Main Methods:
- Molecular mechanics simulations were employed to model the behavior of the annular graphene sheet.
- Analysis focused on identifying wrinkle characteristics such as wave number, orientation, amplitude, and wavelength.
Main Results:
- Wrinkles are confined to an annulus near the inner radius, unlike patterns in rectangular sheets.
- The wave number of the bifurcation wrinkle correlates linearly with the inner radius.
- Wrinkle orientation is constant and independent of the radii ratio.
- Wave amplitude and wavelength are dependent on the magnitude of circular shearing.
Conclusions:
- The study reveals a predictable and unique wrinkling behavior in annular graphene under shear.
- This controlled wrinkling has potential applications in nano-force sensors, tunable electronic/magnetic devices, and stretchable electronics.
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