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Simulation, Fabrication and Characterization of THz Metamaterial Absorbers
Published on: December 27, 2012
3D soft metamaterials with negative Poisson's ratio
Sahab Babaee1, Jongmin Shim, James C Weaver
1School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02138, USA.
Advanced Materials (Deerfield Beach, Fla.)
|July 24, 2013
Summary
Researchers designed novel 3D metamaterials using buckling to achieve a negative Poisson
Area of Science:
- Materials Science
- Mechanical Engineering
- Solid Mechanics
Background:
- Metamaterials offer unique properties not found in natural materials.
- Negative Poisson's ratio (auxetic) behavior is a desirable characteristic for advanced applications.
- Designing 3D auxetic structures remains a significant challenge.
Purpose of the Study:
- To develop a new class of three-dimensional metamaterials exhibiting negative Poisson's ratio.
- To establish a systematic approach for designing and assembling auxetic metamaterials.
- To validate the auxetic properties through experimental and computational methods.
Main Methods:
- Exploiting the phenomenon of buckling in structural design.
- Identifying and selecting auxetic building blocks.
- Developing procedures for the assembly of these blocks into 3D structures.
- Conducting finite element simulations.
- Performing experimental validation.
Main Results:
- Successful design of 3D metamaterials with negative Poisson's ratio.
- Demonstration of auxetic properties through both simulations and experiments.
- Excellent qualitative and quantitative agreement between simulated and experimental results.
- A defined library of auxetic building blocks and assembly procedures.
Conclusions:
- Buckling is an effective mechanism for creating 3D auxetic metamaterials.
- The proposed design methodology enables the creation of predictable auxetic structures.
- Experimental and simulation results confirm the efficacy of the approach.
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