| 摘要 |
PURPOSE:To improve operability by using a hollow iron core. CONSTITUTION:The iron core has a square hollow part 11 at its section and leg parts are formed as openings 12, 13 connected to the hollow part. Such kind of an iron core 10 is constituted by laminating silicon steel plate having high magnetic permeability. In a portable magnetic particle flow detection using yoke method which is provided with the iron core 10, the iron core 10 is formed as an electromagnet by connecting AC 100V having 50/60Hz frequency to the iron core to make current flow into the iron core 10 and the line of magnetic force generated from an electrode is passed through a substance to be tested to induce a magnetic field in the material. If a detect or a flaw exists under the surface of the substance to be tested, the electric resistance of the part is increased, so that magnetic flux is leaked to the surface. The flaw detection can be attained by providing and attracting magnetic particle to the leaked part. |
