抄録
The thickness of the non-magnetic stainless steel overlay-clad of a simulated nuclear reactor pressure vessel (RPV) wall was nondestructively measured by a magnetic method. A part of the wall steel was magnetized with a two-pole magnetic yoke through the overlay-clad, and the magnetic field distribution on the surface of the overlay-clad was measured in the vicinity of one of the poles. The overlay-clad thickness was then determined from the center value and the half-width of the pattern of the measured magnetic field distribution. The thickness can be determined irrespective of the magnetic state of the steels used in the vessel.
