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Characterizing Dissipative Elastic Metamaterials Produced by Additive Manufacturing
Published on: June 28, 2024
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Add-on unidirectional elastic metamaterial plate cloak
Min Kyung Lee1, Yoon Young Kim1,2
1Department of Mechanical and Aerospace Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 151-742, Korea.
Scientific Reports
|February 11, 2016
Summary
This study introduces an add-on metamaterial elastic cloak that avoids embedding in base structures. This novel cloak mitigates stress concentration and restores wave fields without structural alteration.
Area of Science:
- Solid mechanics
- Wave propagation
- Metamaterial applications
Background:
- Metamaterial cloaks manipulate wave propagation for invisibility or insensibility.
- Traditional elastic cloaks require embedding, weakening base structures.
- A non-invasive solution is needed for elastic wave manipulation.
Purpose of the Study:
- To propose and demonstrate a novel add-on metamaterial elastic cloak.
- To investigate its ability to cloak without embedding.
- To assess its performance in stress concentration mitigation and wave field recovery.
Main Methods:
- Design of an add-on annular metamaterial plate cloak using conformal mapping.
- Fabrication of the metamaterial cloak.
- Experimental validation using a thin plate with a hole and the lowest symmetric Lamb wave at 100 kHz.
Main Results:
- Successful demonstration of an add-on metamaterial elastic cloak.
- The cloak effectively mitigated stress concentration around the hole.
- The cloak facilitated recovery of the perturbed elastic wave field.
Conclusions:
- The add-on metamaterial elastic cloak offers a non-invasive method for elastic wave manipulation.
- This technology can be applied as a temporary stress reliever or "stress bandage".
- It avoids structural weakening or permanent alteration of base systems.
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