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Detection of Multi-Layered Bond Delamination Defects Based on Full Waveform Inversion
Jiawei Wen1,2, Can Jiang1, Hao Chen1,2
1Institute of Acoustics, Chinese Academy of Sciences, Beijing 100190, China.
Sensors (Basel, Switzerland)
|June 27, 2024
Summary
This study introduces a new ultrasonic guided wave method for detecting delamination defects in multi-layered structures. The full waveform inversion algorithm offers higher detection efficiency and imaging precision for various defect shapes.
Area of Science:
- Materials Science
- Non-Destructive Testing
- Acoustics
Background:
- Traditional bulk wave delamination detection suffers from low efficiency.
- Guided wave methods using reflected waves are complicated by edge reflections, hindering defect extraction.
Purpose of the Study:
- To develop an innovative approach for detecting delamination defects in multi-layered structures.
- To overcome the limitations of existing delamination detection techniques using ultrasonic guided waves.
Main Methods:
- Utilized finite element modeling to simulate guided wave data acquisition in an aluminum-epoxy bilayer with delamination.
- Applied the full waveform inversion algorithm to reconstruct delamination defects.
- Established an experimental platform using a steel-cement bilayer structure for validation.
Main Results:
- The full waveform inversion algorithm accurately identified both regular and irregular delamination defects.
- Experimental results validated the exceptional imaging precision of the proposed technique.
- The method demonstrated higher detection efficiency compared to traditional pulse-echo methods.
Conclusions:
- The proposed ultrasonic guided wave approach effectively detects delamination defects in multi-layered structures.
- Accurate determination of defect positions and sizes is achievable with improved efficiency.
- This technique offers a promising advancement in non-destructive evaluation for layered materials.
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