Difference in the detection limits of flaws in the depths of multi-layered and continuous aluminum plates using low-frequency eddy current testing

• Published in: NDT & E international : independent nondestructive testing and evaluation Vol. 41; no. 2; pp. 108 - 111
• Main Authors: Yamada, Hironobu, Hasegawa, Teruki, Ishihara, Yudai, Kiwa, Toshihiko, Tsukada, Keiji
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.03.2008; Elsevier Science
• Subjects: Cross-disciplinary physics: materials science; rheology; Eddy current testing; Exact sciences and technology; Fundamental areas of phenomenology (including applications); Low-frequency magnetic field; Magneto-resistive sensor; Materials science; Materials testing; Measurement and testing methods; Non-destructive testing; Physics; Solid mechanics; Structural and continuum mechanics; Non-destructive testing; Low-frequency magnetic field; Magneto-resistive sensor; Eddy current testing; Nondestructive testing; Measurement sensor; Conductivity; Aluminium; Low frequency; Magnetic measurement; Magnetoresistive devices; Detection limit; Metrology; Plates; Defect detection
• ISSN: 0963-8695; 1879-1174
• DOI: 10.1016/j.ndteint.2007.08.004

We examined the difference in the detection limits of flaws in the depths of multi-layered and continuous aluminum plates using low-frequency eddy current testing. The detection limits were measured by using a magneto-resistive sensor. Comparing the frequency of an applied magnetic field, the detection limit at 50 Hz is deeper than that at 1 kHz. Comparing the sample structure, the detection limit in the multi-layered samples is deeper than that in the continuous samples. These results are likely due to the differences in the skin depth and conductivity of the sample.