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06:17
Quantifying the Relative Thickness of Conductive Ferromagnetic Materials Using Detector Coil-Based Pulsed Eddy Current Sensors
Published on: January 16, 2020
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Magnetoelastic Effect Detection with the Usage of Eddy Current Tomography
1Warsaw University of Technology, Institute of Metrology and Biomedical Engineering, 02-525 Warsaw, Poland. p.nowak@mchtr.pw.edu.pl.
Materials (Basel, Switzerland)
|January 26, 2019
Summary
Eddy current tomography can measure small magnetic permeability changes from the magnetoelastic effect in steel under stress. This technique enables quantitative assessment of stress-induced magnetic property variations.
Area of Science:
- Materials Science
- Electromagnetism
- Non-destructive Testing
Background:
- The magnetoelastic effect describes changes in magnetic properties of ferromagnetic materials due to mechanical stress.
- Accurate measurement of these subtle changes is crucial for material characterization and structural health monitoring.
Purpose of the Study:
- To investigate the feasibility of using eddy current tomography (ECT) for quantifying small magnetic permeability variations induced by the magnetoelastic effect.
- To develop and validate a numerical framework for ECT-based magnetoelastic measurements.
Main Methods:
- A ferromagnetic steel sample was subjected to controlled mechanical stresses (up to 30 MPa).
- Eddy current tomography (ECT) was employed to measure magnetic properties.
- Finite Element Method (FEM) simulations were used for forward tomography transformation with known permeability.
- An inverse tomography transformation was developed for determining magnetic permeability from ECT data.
Main Results:
- The study demonstrated the successful application of ECT to detect and quantify small changes in magnetic permeability.
- FEM simulations validated the forward and inverse tomography transformations for known material properties.
- The technique proved capable of measuring stress-induced permeability variations in steel.
Conclusions:
- Eddy current tomography is a viable method for quantitative measurement of the magnetoelastic effect.
- The developed ECT approach allows for non-destructive assessment of stress-related magnetic property changes in ferromagnetic materials.
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