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Detection of disbonds in multi-layer bonded structures using the laser ultrasonic pulse-echo mode
Kuanshuang Zhang1, Shicheng Li1, Zhenggan Zhou2
1Beijing Jinghang Research Institute of Computing and Communication, Beijing 100074, China.
Ultrasonics
|July 16, 2018
Summary
This study introduces a laser ultrasonic method for detecting and sizing disbonds in multi-layer bonded structures. The non-contact technique accurately identifies defects using reflected shear waves, offering practical solutions for material inspection.
Area of Science:
- Materials Science
- Non-Destructive Testing
- Acoustics
Background:
- Disbonds in multi-layer bonded structures pose significant challenges for structural integrity.
- Traditional inspection methods may lack the precision or non-contact capabilities required for complex materials.
Purpose of the Study:
- To investigate the laser ultrasonic technique in pulse-echo mode for detecting disbonds.
- To develop and validate a quantitative method for evaluating the size of detected disbonds.
- To assess the influence of laser spot size on ultrasonic wave characteristics and defect detection.
Main Methods:
- Utilized laser ultrasonic technique in pulse-echo mode for non-destructive evaluation.
- Performed simulations to analyze laser spot size effects and wave-disbond interactions.
- Established a non-contact laser ultrasonic inspection system for experimental verification.
- Employed laser ultrasonic C-scans utilizing reflected shear waves for defect visualization.
Main Results:
- Laser ultrasonic C-scans effectively visualized disbonds within the adhesive bond.
- The proposed quantitative method accurately evaluated disbond sizes within a reasonable error margin.
- Simulation results showed good agreement with experimental data, validating the theoretical models.
Conclusions:
- The laser ultrasonic pulse-echo mode is a practical approach for detecting disbonds in multi-layer bonded structures.
- The combination of laser ultrasonics and the quantitative strategy enables accurate defect detection and size evaluation.
- This non-contact method offers a viable solution for quality control and structural health monitoring.
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