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Updated: Jun 14, 2026
11:08
Fabrication And Characterization Of Photonic Crystal Slow Light Waveguides And Cavities
Published on: November 30, 2012
Boundary echo control of S0-mode lamb waves using gradient phononic crystals.
Haoming Hu1, Hongyu Cui1, Xiaokai Yin1
1School of Naval Architecture & Ocean Engineering, Dalian University of Technology, No.2 Linggong Road, Ganjingzi District, Dalian City, Liaoning Province, People's Republic of China.
Ultrasonics
|June 12, 2026
Summary
This study introduces a novel phononic crystal structure to control S0-mode Lamb wave boundary reflections in ultrasonic testing. The gradient triangular-frame phononic crystal effectively suppresses echoes, enhancing structural health monitoring accuracy.
Area of Science:
- Materials Science
- Acoustics
- Nondestructive Testing
Background:
- Boundary reflections of S0-mode Lamb waves degrade ultrasonic nondestructive testing accuracy.
- Controlling these reflections is crucial for reliable structural health monitoring.
Purpose of the Study:
- To propose and validate a phononic-crystal-based method for S0-mode Lamb wave boundary echo control.
- To design a triangular-frame phononic crystal (TPC) for effective echo suppression.
Main Methods:
- Numerical simulations were performed to assess echo attenuation.
- Band structure analysis was used to understand wave propagation and mode conversion.
- Experimental validation compared the TPC with conventional damping materials.
Main Results:
- The proposed triangular-frame phononic crystal (TPC) structure effectively attenuates boundary echoes.
- A gradient TPC configuration further enhanced echo suppression performance.
- Experimental results showed the gradient TPC significantly outperformed damping clay.
Conclusions:
- The phononic-crystal-based approach offers a viable solution for controlling S0-mode Lamb wave boundary reflections.
- This method has significant potential for advancing ultrasonic guided-wave-based structural health monitoring.
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