抄録
A new method is presented by which grains in grain-oriented silicon steel can be imaged clearly through an overcoating. A miniaturized magnetic anisotropy probe consisting of an exciting coil and a pickup coil is used as a scanning device. Each grain of the silicon steel is detected as a region within which the easy axis of the magnetic anisotropy is determined to lie in a common direction. Because of its built-in spatial differentiation, the probe is also sensitive to magnetic dis-continuities in a specimen. With these two probe attributes, grains are imaged with the grain boundaries enhanced. The alignment of the easy axis, that is, the [100] direction projected onto the scanning plane with respect to the rolling direction, is displayed on a gray-scale level. Imaging results are shown for highly grain-oriented silicon steel sheets.
