Magnetic measurement device

Patent metadata

Field	Value
Publication number	US-9702945-B2
Application number	US-201214374640-A
Country	US
Kind code	B2
Filing date	Dec 13, 2012
Priority date	Jan 26, 2012
Publication date	Jul 11, 2017
Grant date	Jul 11, 2017

Abstract

A magnetic measurement device which can measure the magnetic characteristics in a microregion of a thin plate magnetic sample. After a magnetic sample is applied by a magnetic field and magnetized accordingly, by scanning the magnetic sample using a measuring part, the magnetic flux leakage in the magnetic sample can be measured. The magnetic flux leaks outside by magnetizing a first region and a second region of the magnetic sample in reciprocally opposite directions and reducing the demagnetizing field. Specifically, a magnetic field generating part with at least a pair of magnetic poles is used to perform the magnetization of multiple poles, or the magnetic field generating part applies a damped oscillation magnetic field to perform the magnetization, or a local magnetic field generating part which applies an alternating magnetic field and scans the surface of the sample at the same time is used to perform the magnetization.

First claim

What is claimed is:

1. A magnetic measurement device for measuring remanent magnetization of a plate magnetic sample, the plate magnetic sample having a flat shape with a flat major surface and a magnetization direction perpendicular to the flat major surface, the magnetic measurement device comprising:
a magnetic field generating part which comprises at least a pair of adjacent magnetic poles with different signs, and magnetizes said magnetic sample by the magnetic poles by applying a magnetic field and magnetizing a first region of the flat major surface of the magnetic sample in a first direction and a second region of the flat major surface of the magnetic sample in a second direction, the first direction and the second direction being perpendicular to the flat major surface of the magnetic sample and opposite to each other, and forming a boundary in the magnetic sample between the first region and the second region, the first region and the second region being adjacent to each other via the boundary; and
a measuring part which measures the magnetic field of the magnetic sample magnetized by the magnetic field generating part and outputs the magnetic field as the remanent magnetization of the magnetic sample.

2. The magnetic measurement device of claim 1 , wherein, the magnetic field generating part produces a damped oscillation magnetic field to magnetize the magnetic sample.

3. The magnetic measurement device of claim 1 , wherein, the magnetic field generating part scans the flat major surface of the magnetic sample while simultaneously produces an alternating magnetic field to magnetize the magnetic sample.

Assignees

• Tdk Corp

Inventors

• Suzuki Kenichi
• Chikamatsu Tsutomu
• Ogawa Akio
• Choi Kyung-Ku
• Hashimoto Ryuji

Classifications

• G01R33/10 Primary

  Plotting field distribution {; Measuring field distribution} · CPC title

• G01R33/12 Primary

  Measuring magnetic properties of articles or specimens of solids or fluids (involving magnetic resonance G01R33/20) · CPC title

• G01R33/1215

  Measuring magnetisation; Particular magnetometers therefor (G01R33/14 takes precedence; electrodynamic magnetometers G01R33/028) · CPC title