Vector-Based Eddy-Current Testing Method

We present a type of eddy-current testing (ECT) method based on measuring the reaction of the Lorentz force by using a small permanent magnet (PM) as the probe. The means of measuring impedance is superseded by measuring force. By analyzing the variations in different components of the reaction of Lorentz force, the defects characteristics within the measured conductor can be revealed. The results indicate that the vector-based eddy-current testing method obtains good quantitative results and precisely evaluates the lift-off effect during measurement along two orthogonal directions. Numerical simulations are performed to provide supports for the experimental results. The method described in this paper may have great potential for use in industrial nondestructive testing applications.

[1]  Octavian Postolache,et al.  Detection and characterization of defects using GMR probes and artificial neural networks , 2011, Comput. Stand. Interfaces.

[2]  Javier García-Martín,et al.  Non-Destructive Techniques Based on Eddy Current Testing , 2011, Sensors.

[3]  Baldev Raj,et al.  An artificial neural network for eddy current testing of austenitic stainless steel welds , 2002 .

[4]  V. Elings,et al.  Fractured polymer/silica fiber surface studied by tapping mode atomic force microscopy , 1993 .

[5]  Robert P. Uhlig,et al.  Lorentz Force Eddy Current Testing: a Prototype Model , 2012 .

[6]  Francisco Caleyo,et al.  Rapid estimation of artificial near-side crack dimensions in aluminium using a GMR-based eddy current sensor , 2012 .

[7]  Catalin Mandache,et al.  Transient and harmonic eddy currents: Lift-off point of intersection , 2006 .

[8]  Wang Xiaodong,et al.  Lorentz force particle analyzer with an array probe based on speckle pattern interferometry , 2017 .

[9]  Zhen Tao,et al.  A magnetostatic force inspection method for monitoring the oscillation marks of continuous casting , 2015 .

[10]  Richard Binns,et al.  Analysis of the Liftoff Effect of Phase Spectra for Eddy Current Sensors , 2007, IEEE Transactions on Instrumentation and Measurement.

[11]  A. Monfardini,et al.  Cantilever anemometer based on a superconducting micro-resonator: application to superfluid turbulence. , 2012, The Review of scientific instruments.

[12]  Rene Moreau,et al.  An innovative contactless method for detecting defects in electrical conductors by measuring a change in electromagnetic torque , 2015 .

[13]  M. Maeda,et al.  A New Eddy Current Surface Probe for Short Flaws with Minimal Lift‐Off Noise , 2003 .

[14]  Bo Wang,et al.  Lorentz force particle analyzer , 2016 .

[15]  Gui Yun Tian,et al.  Reduction of lift-off effects for pulsed eddy current NDT , 2005 .

[16]  A. Thess,et al.  Lorentz force velocimetry. , 2006, Physical review letters.

[17]  Marek Ziolkowski,et al.  Finite Element Analysis of Nondestructive Testing Eddy Current Problems With Moving Parts , 2013, IEEE Transactions on Magnetics.

[18]  Joachim Peinke,et al.  Laser-cantilever anemometer: A new high-resolution sensor for air and liquid flows , 2005 .

[19]  Artur Lopes Ribeiro,et al.  Velocity induced eddy currents technique to inspect cracks in moving conducting media , 2013, 2013 IEEE International Instrumentation and Measurement Technology Conference (I2MTC).