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Fabrication and Characterization of Thickness Mode Piezoelectric Devices for Atomization and Acoustofluidics
Published on: August 5, 2020
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EMAT design for minimum remnant thickness gauging using high order shear horizontal modes
Aurélien Thon1, Pierre Bélanger1
1Département de Génie Mécanique, École de Technologie Supérieure, 1100, Rue Notre-Dame Ouest, Montréal, Québec H3C 1K3, Canada.
Ultrasonics
|March 22, 2019
Summary
This study introduces a novel ultrasonic guided wave technique for detecting and sizing corrosion in industrial structures. Electromagnetic acoustic transducers (EMATs) enable precise thickness measurements, even in hard-to-reach areas.
Area of Science:
- Materials Science
- Non-Destructive Testing
- Ultrasonic Wave Propagation
Background:
- Corrosion detection and sizing are critical for industries like oil and gas and petrochemicals.
- Inspecting partially accessible structures (e.g., pipes under insulation) presents significant challenges.
- Existing methods can be time-consuming and difficult for complex geometries.
Purpose of the Study:
- To develop and validate a novel ultrasonic guided wave technique for accurate corrosion assessment.
- To optimize the use of electromagnetic acoustic transducers (EMATs) for exciting multiple ultrasonic modes.
- To enable reliable thickness gauging in challenging inspection scenarios.
Main Methods:
- Utilized the cutoff frequency-thickness product principle of high-order ultrasonic guided wave modes.
- Employed analytical and multiphysics finite element simulations to optimize EMAT design.
- Experimentally validated the technique on aluminum plates with simulated corrosion.
Main Results:
- Demonstrated that thickness variations act as a low-pass filter for guided wave modes.
- Optimized EMAT excitation to control the number of modes and beam width.
- Achieved a thickness resolution of 2 mm in a 10 mm aluminum plate.
Conclusions:
- The developed ultrasonic guided wave technique is effective for corrosion detection and sizing.
- EMATs provide precise control over mode excitation for improved measurement accuracy.
- This method offers a viable solution for inspecting difficult-to-access industrial components.
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