Features of Linear Defects Eddy Current Images Obtained with Use of Ferrite Garnet Films

Abstract

The influence of most physical factors on the revelation ability of magneto-optic eddy current defectoscopy of linear defects in metallic objects is investigated. Uniaxial anisotropy multi-component Bi-substituted garnet film is used as the sensor element. The efficiency of visualization depends on frequency and amplitude of the inducer’s electric current and the biasing magnetic field. Optimal values of these parameters are obtained. It is shown that the alternative magnetic field exerts the most influence on the eddy current magneto-optic image.

Investigation of welds by the method of the magneto-optical eddy current flaw detection

“…In [3,4] the influence of different characteristics of the flaw detector, such as the frequency of the excitation current, the magnitude and sign of the acting magnetic fields, on the MOEC image was studied.…”

“…Visualization of the DS is carried out with the help of the Faraday Effect, as a result of which the rotation of the plane of polarization of the transmitted light occurs as a function of the direction of the local magnetization. The scheme and principle of operation are described in more detail in [3].…”