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Updated: Jun 24, 2026
06:17
Quantifying the Relative Thickness of Conductive Ferromagnetic Materials Using Detector Coil-Based Pulsed Eddy Current Sensors
Published on: January 16, 2020
Highly sensitive anisotropic magnetoresistance magnetometer for Eddy-current nondestructive evaluation
1Superconducting Materials Center, National Institute for Materials Science, 1-2-1 Sengen Tsukuba Ibaraki 305-0047, Japan. he.dongfeng@nims.go.jp
The Review of Scientific Instruments
|April 2, 2009
Summary
We developed a sensitive anisotropic magnetoresistance (AMR) magnetometer using the HMC1001 sensor. This device achieved high magnetic field resolution, enabling eddy-current nondestructive evaluation in unshielded environments.
Area of Science:
- Physics
- Materials Science
- Electrical Engineering
Background:
- Anisotropic magnetoresistance (AMR) sensors offer high sensitivity for magnetic field detection.
- Developing robust magnetometers is crucial for various scientific and industrial applications.
Purpose of the Study:
- To develop a sensitive magnetometer using a commercial AMR sensor (HMC1001).
- To evaluate the performance of the AMR magnetometer in an unshielded environment for eddy-current nondestructive evaluation.
Main Methods:
- Utilized a commercially available HMC1001 anisotropic magnetoresistance (AMR) sensor.
- Operated the sensor in both amplifier and feedback modes.
- Biased the AMR sensor with a 24 V voltage supply.
Main Results:
- Achieved a magnetic field sensitivity of approximately 3.2 mV/V G.
- Demonstrated magnetic field resolutions of 12 pT/√Hz at 1 kHz and 20 pT/√Hz at 100 Hz.
- Successfully applied the AMR magnetometer for eddy-current nondestructive evaluation.
Conclusions:
- The developed AMR magnetometer is highly sensitive and suitable for practical applications.
- The device performs effectively in unshielded environments, proving its utility in real-world scenarios.
- This magnetometer is a valuable tool for eddy-current nondestructive evaluation.
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