TY - JOUR
T1 - Detection of back-side pit on a ferrous plate by magnetic flux leakage method with analyzing magnetic field vector
AU - Tsukada, Keiji
AU - Yoshioka, Mitsuteru
AU - Kawasaki, Yoshihiko
AU - Kiwa, Toshihiko
N1 - Copyright:
Copyright 2010 Elsevier B.V., All rights reserved.
PY - 2010/6
Y1 - 2010/6
N2 - We have developed a magnetic flux leakage (MFL) system using magnetic resistive (MR) sensors for detecting two dimensional magnetic field components, and an induction coil that generates low magnetic field strengths and extremely low frequencies. The signal at each scanned measurement point (i) was divided by the signal strength Mmes,i and phase αi by a lock-in amplifier. Using the strength Mmes,i and phase αi, we calculated the imaginary part of the signal using the common phase β. By optimization of the common phase β to the imaginary part, the analyzed scanning data curve was shown to be effective in estimating the size (depth and diameter) of back-side pits on a ferrous plate. Comparing the two dimensional magnetic field components of leakage, the imaginary part of the y-component parallel to the induced magnetic field was found to be suitable for detecting the back-side pits.
AB - We have developed a magnetic flux leakage (MFL) system using magnetic resistive (MR) sensors for detecting two dimensional magnetic field components, and an induction coil that generates low magnetic field strengths and extremely low frequencies. The signal at each scanned measurement point (i) was divided by the signal strength Mmes,i and phase αi by a lock-in amplifier. Using the strength Mmes,i and phase αi, we calculated the imaginary part of the signal using the common phase β. By optimization of the common phase β to the imaginary part, the analyzed scanning data curve was shown to be effective in estimating the size (depth and diameter) of back-side pits on a ferrous plate. Comparing the two dimensional magnetic field components of leakage, the imaginary part of the y-component parallel to the induced magnetic field was found to be suitable for detecting the back-side pits.
KW - Low-frequency magnetic field
KW - Magnetic flux leakage
KW - Magneto-resistive sensor
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U2 - 10.1016/j.ndteint.2010.01.004
DO - 10.1016/j.ndteint.2010.01.004
M3 - Article
AN - SCOPUS:77950593178
VL - 43
SP - 323
EP - 328
JO - NDT and E International
JF - NDT and E International
SN - 0963-8695
IS - 4
ER -