| 摘要 |
PURPOSE:To enable the measurement of a coercive force of a test piece simply at a high accuracy by a method wherein a test piece is magnetized in a solenoid, rotated in front of a head of a detection coil and then, a specified demagnetization is done with a demagnetizing coil. CONSTITUTION:A test piece is magnetized with a magnetizing coil 12 in a solenoid 10 and rotated in front of a head of a detection coil 28 so that the magnetic flux thereof is caused to cross the detection coil 28 at the right angle thereto to generate an induced voltage (e) by an electromagnetic induction. Then, a magnetic field necessary for cancelling the induced voltage (e) is applied anew by a demagnetizing coil 14 from outside to calculate the strength of an external magnetic field necessary for making the induced voltage (e) zero to be used as a coercive force. Thus, the coercive force of the test piece can be measured very simply at a high accuracy. |
