ELECTROMAGNETIC ULTRASONIC PROBE

摘要

PROBLEM TO BE SOLVED: To improve a flaw detection capability and a measurement capability by making a magnet structure stronger or smaller. SOLUTION: The electromagnetic ultrasonic probe comprises one or more pairs of magnet arrangement units which periodically arrange many prism-shaped permanent magnets and apply a magnetic field to a member to be inspected, and a coil which generates or detects an eddy current in the member to be inspected. The magnet arrangement unit 30 comprises a periodic arrangement structure in which primary magnets 32a and auxiliary magnets 32b are combined with their height direction aligned, wherein the primary magnets 32a are magnetized in the height direction and are arranged so that their magnetization directions are alternatingly opposed, and the auxiliary magnets 32b are magnetized in the thickness direction and are placed between the primary magnets and at both the ends so that their magnetization directions are alternatingly reversed. The surface of the north pole side of the primary magnet which is in contact with the surface of the north pole side of the auxiliary magnet is set to be a magnet working surface. COPYRIGHT: (C)2005,JPO&NCIPI