The Study Of Giant Magneto-Impedance Effect And Sensor Model Of Fe-Cu-Nb(V)-Si-B Nanocrystalline Alloy

With the development of information technology which are related to mechanical and electronic equipment applying to electric power, medical treatment, car, industrial robot and testing facility, there are increasing demand to magnetosensor with high capability. Recently, a new sensitive giant magneto-impedance effect with the sensitivity of 12%¹20%/Oe at room temperature was found in some new soft magnetic material. Researching material with giant magneto-impedance play a important role in theory and application of magnetoelectronics.Aiming at giant magneto-impedance effect in Fe-base nanocrystalline alloy and application in magnetosensor, the follosings are some creative aspects:1. Phenomenon that Temperature of annealing, frequency of current, magnetic field impose on GMI(Giant Magneto-impedance) of nanocrystalline alloy samples Fe_72.7Nb₂Cu₁V_1.8Si_13.5B₉ and Fe_73.5Cu₁Nb₃Si_13.5B₉ have been observed. Temperature of annealing, frequency of current, magnetic field effect GMI of the two nanocrystalline alloy obviously. The higher value of the magnetoimpedance rates for samples can be gained both at frequency of current between 0.5MHz and 1.5MHz. and at magnetic field between 1Oe and 4Oe. Samples of Fe_72.7Nb₂Cu₁V_1.8Si_13.5B₉ annealed at temperatures between 520℃and 580℃can be related to the higher value of the magnetoimpedance rates. In order to get higher value of the magnetoimpedance rates, samples of Fe_72.7Nb₂Cu₁V_1.8Si_13.5B₉ must be annealed at temperatures between 540℃and 580℃. this is because element V influence the value of the magnetoimpedance rates on the samples of Fe_72.7Nb₂Cu₁V_1.8Si_13.5B₉. there have not been the reports on giant magneto-impedance effect of Fe_72.7Nb₂Cu₁V_1.8Si_13.5B₉.2. based on the result from giant magneto-impedance effect in Fe_72.7Nb₂Cu₁V_1.8Si_13.5B₉ nanocrystalline alloy, the model of sensor about giant magneto-impedance effect to measure speed of wheel have been studied. Seilor current adapt samples having giant magneto-impedance effect to supply AC source. Its parameters can be calculated through computer program. The seilor current is proved to be a right oscillator through operating point analysis, temperature sweep and transient analysis by Protel99. Filter and voltage comparator can transform the sine wave out of seilor current into square wave. The signal of magnetic field between 0Oe and 2Oe can be transformed into the signal square wave with same period between 0V and 6V through the sensor including component having giant magneto-impedance, seilor current, filter and voltage comparator. This square can take count of frequency of wheel running. About this kind of the model of of sensor about giant magneto-impedance effect, there have not been reports in the world.