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Cortical Bone Assessment Using Ultrasonic Guided Waves: A Reproducibility Study in a Healthy Population
Published on: January 31, 2025
719
Guided Wave Phase Velocity Dispersion Reconstruction Based on Enhanced Phased Spectrum Method.
Vykintas Samaitis1, Liudas Mažeika1
1Prof. K. Baršauskas Ultrasound Research Institute, Kaunas University of Technology, K. Baršausko St. 59, LT-51423 Kaunas, Lithuania.
Materials (Basel, Switzerland)
|February 25, 2022
Summary
This study introduces a new phase velocity reconstruction method for ultrasonic guided waves in composite laminates. The technique accurately detects defects and estimates material properties, enhancing structural integrity assessments.
Area of Science:
- Materials Science
- Mechanical Engineering
- Non-Destructive Testing
Background:
- Fibre-reinforced composites offer high stiffness-to-weight ratios, crucial for meeting CO2 emission standards in engineering.
- Limited inter-laminar strength in composites can lead to defects, compromising structural integrity and fatigue life.
- Ultrasonic guided waves are vital for assessing the health of composite structures, with phase velocity being a key characteristic.
Purpose of the Study:
- To develop and validate a novel phase velocity reconstruction approach for ultrasonic guided waves.
- To accurately estimate phase velocity for defect detection, material property estimation, and dispersion analysis in composite laminates.
- To overcome limitations of conventional methods, enabling application with narrowband transducers and complex wave modes.
Main Methods:
- Proposed a phase velocity reconstruction approach utilizing the phase-shift method with frequency sweep excitation.
- Estimated phase velocity at specific frequency harmonics, suitable for narrowband piezoelectric transducers.
- Validated the technique through finite element simulations and experimental studies on isotropic and anisotropic structures.
Main Results:
- The proposed method accurately reconstructs phase velocity dispersion curves for direct, converted, and multiple co-existing modes.
- Validation confirmed high accuracy, with a relative error of ±4% compared to theoretical predictions.
- Successful reconstruction of phase velocity dispersion was achieved within the -20 dB bandwidth of the transducer.
Conclusions:
- The developed phase velocity reconstruction technique offers a highly accurate and versatile method for analyzing ultrasonic guided waves in composites.
- This approach enhances the capability for defect detection and material characterization in composite structures.
- The method's applicability to narrowband transducers and complex wave modes represents a significant advancement in non-destructive evaluation.
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