MAGNETO-OPTICAL METHOD FOR TESTING ARTICLES

摘要

The invention relates to the field of applied magneto-optics, in particular, to devices based on the Faraday magneto-optical effect. The aim of the invention consists in testing articles made of soft magnetic and non-magnetic conducting materials, providing for the possibility of identification of articles during their marking and for checking of non-sanctioned opening of articles. The invention is based on registration of the magnetic leakage field of the article by visualization of the distribution of magnetization in a magneto-optical film which is placed near the surface of the article. Before the registration in the check zone of the article, a magnetic field is generated by permanent magnets or by means of excitation of eddy currents. For the purpose of identification of the article it is marked by a symbol applied by changing the relief and/or the structure of the internal surface and/or of the volume of the article. The invention is industrially applicable in magneto-optical defectoscopes intended for articles made of soft magnetic and non-magnetic conducting materials, for hidden marking of articles made of various materials, for hidden sealing of rooms, safes, waggons, containers, trunks, suitcases etc...