10.14489/td.2024.02.pp.015-028

2024, 02 February

DOI: 10.14489/td.2024.02.pp.015-028

Shkatov P. N.
A MODEL OF THE MAGNETIC FIELD OF A CRACK SURROUNDED BY A UNIFORM EDDY CURRENT
(pp. 15-28)

Abstract. Eddy current probes with uniform eddy currents, which are increasingly often used in practice, use the measurement of various components of the magnetic field of a defect arising when the current flows around surface cracks. The patterns of formation of components of the magnetic field strength of the defect that are orthogonal to the surface of the tested object (normal) Hn, as well as parallel to the plane of the crack (tangential) Ht are quite obvious and allow us to establish that their extreme values arise in the plane of the crack above its ends and center, respectively. At the same time, there does not exist a satisfactory model of the mechanism of formation of the axial component Hx, directed perpendicular to the crack plane. Both experiments and numerical calculations show the complex character of the function Hx. It has 4 regions with different directions in the vicinity of the crack, and its four extrema arise at a certain distance from the plane of the crack and are shifted relative to the axis of symmetry. The lack of a simple model of the formation of the function Hx makes it difficult to understand the functioning and develop appropriate eddy current transducers. The present paper addresses this problem.

Keywords: uniform eddy current, axial component of the magnetic field of the defect, a model of formation.

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P. N. Shkatov (MIREA – Russian Technological University, Moscow, Russia) E-mail: Данный адрес e-mail защищен от спам-ботов, Вам необходимо включить Javascript для его просмотра.

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