A Sensitive Magnetic Field Sensor Utilizing the Giant Magneto-Impedance Effect in Field-Annealed Co-Based Amorphous Ribbons

作者：Jiang Yanwei; Fang Jiancheng; Wang Sansheng^*; Song Yujun

来源：Sensor Letters, 2010, 8(2): 314-319.

DOI：10.1166/sl.2010.1271

• Giant Magneto-Impedance (GMI)
• Magnetic Sensor
• Co-Based Amorphous Ribbons
• Field-Annealing
• Open-Loop
• Closed-Loop

A large giant magneto-impedance (GMI) effect was observed in Co(69)Fe(4)Si(12)B(15) amorphous ribbon after it was annealed at a temperature of 450 degrees C for 30 min in a 10 Oe annealing field along the transverse direction of the ribbon. A maximum GMI ratio of 320% and a sensitivity of about 200%/Oe were obtained under an excitation AC current at a frequency of 10 MHz, which is helpful in the fabrication of high sensitivity magnetic sensors. Based on these excellent GMI properties, a sensitive magnetic field sensor was developed utilizing the abovementioned field-annealed amorphous ribbon as the sensing element. The performance of the sensor was tested in open-loop and closed-loop conditions. Compared with the open-loop testing, the sensor shows a better linearity of 0.59% and a larger measuring range (-2.5 similar to 2.5 Oe) in the closed-loop testing. The closed-loop testing also shows a sensitivity of 0.34 V/Oe compared with the sensitivity of 2.3 V/Oe in the open-loop testing. The designed sensor can be applied to detect the value and direction of geomagnetic fields, which have practical applications in geomagnetic navigation.

• 出版日期2010-4
• 单位北京航空航天大学