A magnetic field sensor based on flaky Terfenol-D material and dual fiber grating

Area of Science:

• Optoelectronics
• Materials Science
• Sensor Technology

Background:

• Magnetic field measurement is crucial for safety, disaster prevention, and geological exploration.
• Existing fiber optic magnetic field sensors suffer from low sensitivity and temperature cross-sensitivity.

Purpose of the Study:

• To develop an improved fiber optic magnetic field sensor with enhanced sensitivity and reduced temperature interference.
• To address the limitations of current magnetic field sensing technologies.

Main Methods:

• A sensor model was established using SolidWorks, analyzing strain transfer theory.
• Flaky Terfenol-D material was prestressed to optimize sensor performance.
• A dual fiber Bragg grating configuration was employed for temperature decoupling.

Main Results:

• The sensor achieved a magnetic field sensitivity of 53.44 pm/mT and a resolution of 37.4 μT.
• Optimal prestress was found to be 3.5 MPa, with a temperature sensitivity of 0.23 pm/°C.
• The dual fiber differential method effectively compensated for temperature interference.

Conclusions:

• The proposed sensor offers high sensitivity and accuracy for magnetic field measurement.
• The temperature decoupling method significantly improves measurement reliability in varying thermal conditions.
• This technology is suitable for magnetic field sensing in harsh environments with electromagnetic interference.