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Updated: Jul 13, 2025
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Ultrasonic Welding of Thermoplastic Composite Coupons for Mechanical Characterization of Welded Joints through Single Lap Shear Testing
Published on: February 11, 2016
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Validation of zero-group-velocity feature guided waves in a welded joint
Xiangdi Meng1, Mingxi Deng1, Weibin Li2
1College of Aerospace Engineering, Chongqing University, Chongqing 400044, China.
Ultrasonics
|October 11, 2023
Summary
This study confirms zero-group-velocity (ZGV) feature guided waves (FGWs) in welded joints using advanced modeling. These ZGV-FGWs offer new possibilities for nondestructive testing in complex structures.
Area of Science:
- Solid mechanics
- Wave propagation
- Nondestructive testing
Background:
- Zero-group-velocity (ZGV) Lamb waves are well-researched in elastic plates for nondestructive testing.
- Limited research exists on ZGV modes in complex structures like welded joints.
Purpose of the Study:
- To investigate the presence and characteristics of ZGV feature guided waves (FGWs) in a welded joint.
- To extend the understanding of ZGV phenomena beyond simple elastic plates.
Main Methods:
- Two-dimensional (2D) finite element (FE) modeling to analyze response spectra and identify resonance.
- Three-dimensional (3D) time-step FE method to investigate resonance modes.
- Spatial 2D and short-time Fourier transforms for signal analysis.
- Semi-analytical finite element method with perfectly matched layer for acoustic field analysis.
Main Results:
- Resonance phenomena were identified in the response spectra of the welded joint.
- Both non-propagation (local resonance) and propagation modes were verified.
- Propagation modes in the welded joint exhibit zero-group-velocity (ZGV) characteristics.
- ZGV characteristics were confirmed for feature guided waves (FGWs) at resonance frequencies, termed ZGV-FGWs.
Conclusions:
- The existence of ZGV-FGWs in welded joints is established.
- This research provides a foundation for future studies on ZGV-FGWs in complex structural components.
- The findings open new avenues for advanced nondestructive testing applications.
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