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Cortical Bone Assessment Using Ultrasonic Guided Waves: A Reproducibility Study in a Healthy Population
Published on: January 31, 2025
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Estimating the Depths of Normal Surface Notches Using Mode-Conversion Waves at the Bottom Tip
Qianghua Pan1, Jiawei Xu2, Wenbo Li1
1China Special Equipment Inspection and Research Institute, Beijing 100029, China.
Sensors (Basel, Switzerland)
|August 10, 2024
Summary
This study introduces a laser-ultrasonic method to measure surface crack depths using time-domain analysis of wave propagation. The technique accurately determines crack depth by analyzing time delays in reflected and scattered waves.
Area of Science:
- Materials Science
- Non-Destructive Testing
- Acoustics
Background:
- Surface cracks pose significant risks in structural integrity.
- Accurate depth measurement of surface cracks is crucial for material assessment.
- Existing methods may lack precision or require physical contact.
Purpose of the Study:
- To develop and validate a non-contact laser-ultrasonic method for quantitative surface crack depth measurement.
- To analyze the two-parameter inversion problem related to crack width and depth.
- To refine depth measurement formulas using time-domain wave analysis.
Main Methods:
- Utilizing a laser-based ultrasonic technique in the time domain.
- Analyzing time delays between reflected and scattered waves.
- Incorporating wave scattering from crack tips and mode transformations.
Main Results:
- A corrected depth measurement formula including the term "2wβ" was derived.
- Experimental validation was performed on aluminum and steel specimens.
- The method demonstrated effectiveness in quantitatively measuring crack depths.
Conclusions:
- A novel, effective approach for crack depth measurement using laser ultrasound is presented.
- The time-domain properties of surface wave propagation are key to this method.
- This non-contact technique offers a reliable solution for assessing surface crack dimensions.
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