Hybrid of Eddy Current Probe based on Permanent Magnet and GMR Sensor


  • Moneer A Faraj Faculty of Electrical and Electronics, University Malaysia Pahang, Malaysia
  • Fahmi Samsuri Faculty of Electrical and Electronics, University Malaysia Pahang, Malaysia
  • Ahmed N AbdAlla Faculty of Electronic Information Engineering, Huaiyin Institute of Technology, Huaian, Jiangsu, China


Eddy Current Testing, GMR Sensor, Defect Detection, Non-destructive Testing, Calibration,


The eddy current testing (ECT) is used to inspect a material to determine its properties without destroying its utility. The applications include detection of flaws in aircrafts, pipeline, etc. An ECT is a weak sensitivity to a subsurface defect. Applications of giant magnetic sensors (GMR) are increasingly applied to the measurement of weak magnetic fields related to the currents they cause. In this paper, GMR sensor with magnet bar (permanent) is utilized. The proposed probe system is utilized to study the impact of the width and depth defect on the signal of eddy current testing. The maximum depth of flaw in a mild steel can be revealed by using this probe. The graph of the difference between the peak amplitude and the penetration depth of each slot of a different width of the two bands of mild steel shows the increase of the signal for each slot and flat above 3mm. The experimental result proves the inability of a PMGMR probe to detect a defect at a depth of 3mm on a surface defect.


D. Rifai, A. N. Abdalla, K. Ali, and R. Razali, "Giant Magnetoresistance Sensors: A Review on Structures and NonDestructive Eddy Current Testing Applications," Sensors, vol. 16, p. 298, 2016.

J. García-Martín, J. Gómez-Gil, and E. Vázquez-Sánchez, "Nondestructive techniques based on eddy current testing," Sensors, vol. 11, pp. 2525-2565, 2011.

J.-T. Jeng, G.-S. Lee, W.-C. Liao, and C.-L. Shu, "Depth-resolved eddy-current detection with GMR magnetometer," Journal of Magnetism and Magnetic Materials, vol. 304, pp. e470-e473, 2006.

K. B. Ali, A. N. Abdalla, D. Rifai, and M. A. Faraj, "Review on system development in eddy current testing and technique for defect classification and characterization," IET Circuits, Devices & Systems, 2017.

T. Dogaru and S. T. Smith, "Giant magnetoresistance-based eddycurrent sensor," IEEE Transactions on Magnetics, vol. 37, pp. 3831- 3838, 2001.

C. S. Angani, H. G. Ramos, A. L. Ribeiro, and T. J. Rocha, "Evaluation of transient eddy current oscillations response for thickness measurement of stainless steel plate," Measurement, vol. 90, pp. 59-63, 2016.

F. Vacher, F. Alves, and C. Gilles-Pascaud, "Eddy current nondestructive testing with giant magneto-impedance sensor," NDT & E International, vol. 40, pp. 439-442, 2007.

D. Rifai, N. Abdalla, N. Khamsah, K. Ali, and R. Ghoni, "Defect Signal Analysis for Nondestructive Testing," Proceedings of the FluidsChR, 2015.

C. S. Angani, H. G. Ramos, A. L. Ribeiro, T. J. Rocha, and P. Baskaran, "Lift-Off Point of Intersection Feature in Transient Eddy-Current Oscillations Method to Detect Thickness Variation in Stainless Steel," IEEE Transactions on Magnetics, vol. 52, pp. 1-8, 2016.

J. Bowler and M. Johnson, "Pulsed eddy-current response to a conducting half-space," IEEE Transactions on magnetics, vol. 33, pp. 2258-2264, 1997.

S. Udpa and P. Moore, "Nondestructive testing handbook: electromagnetic testing," Amer Society for Nondestructive, 2004.

J. Xin, N. Lei, L. Udpa, and S. S. Udpa, "Nondestructive inspection using rotating magnetic field eddy-current probe," IEEE Transactions on Magnetics, vol. 47, pp. 1070-1073, 2011.

M. A. Faraj, F. Samsuri, A. N. Abdalla, D. Rifai, and K. Ali, "Adaptive Neuro-Fuzzy Inference System Model Based on the Width and Depth of the Defect in an Eddy Current Signal," Applied Sciences, vol. 7, p. 668, 2017.

D. Rifai, A. N. Abdalla, R. Razali, K. Ali, and M. A. Faraj, "An Eddy Current Testing Platform System for Pipe Defect Inspection Based on an Optimized Eddy Current Technique Probe Design," Sensors, vol. 17, p. 579, 2017.

T. Y. Poon, N. C. F. Tse, and R. W. H. Lau, "Extending the gmr current measurement range with a counteracting magnetic field," Sensors, vol. 13, pp. 8042-8059, 2013.

Y.-J. Kim and S.-S. Lee, "Eddy current probes of inclined coils for increased detectability of circumferential cracks in tubing," NDT & E International, vol. 49, pp. 77-82, 2012.

R. Ghoni, M. Dollah, A. Sulaiman, and F. M. Ibrahim, "Defect characterization based on eddy current technique: Technical review," Advances in Mechanical Engineering, vol. 6, p. 182496, 2014.




How to Cite

A Faraj, M., Samsuri, F., & N AbdAlla, A. (2018). Hybrid of Eddy Current Probe based on Permanent Magnet and GMR Sensor. Journal of Telecommunication, Electronic and Computer Engineering (JTEC), 10(1-2), 7–11. Retrieved from https://jtec.utem.edu.my/jtec/article/view/3312