Giant Magnetoimpedance Measurement And Application Of Glass-Covered Amorphous Wire

Giant Magnetoimpedance effect, as a new phenomenon founded in the field of soft magnetic materials in the 1990s, means that impedance of some magnetic materials changes sensitively with DC magnetic field. New type of magnetic sensors with high sensitivity, quick response and low power consumption can been developed using this effect, thus the mechanism of action, the employment of new materials and new technology, the seeking of new applications attract considerable research interest in the field of soft magnetic materials. Because it's small size, low cost and high strength, the wire shape amorphous alloy being one with the most notable GMI effect materials, has even more enormous foreground of application.So far, the reported studies have focused on the research material composition, sample forms, preparation technology, and frequency range and research conclusion. Overseas, the impedance analysis is often used to measure material characteristics in a wide frequency range. But it is very expensive, so that most domestic research institutions can not afford to buy; it has become one of the reasons for the slow domestic research. At present, special measuring instrument to be used in the GMI effects have domestic rarely been researched. Meanwhile, GMI effect sensor is rarely reported in the study.Multifunctional equipment has been exploited for measuring GMI effect of glass-covered alloy fiber based on virtual instrument technology with following merits: friendly interface, simplicity for operating, low cost, measure frequency bandwidth. The equipment can be used to quickly measureΔZ /Z.Fe-based alloy wire GMI effect was measured by this measuring equipment. The relationship between GMI effect and AC frequency, external magnetic field were measured. Finally, the measuring results are briefly analyzed.A kind of new magnetic sensor was studied and built with glass-covered Fe-based amorphous wire based on earlier studies. Sensor structure and principle was first introduced. Quartz crystal oscillator was used as a high-frequency excitation signal source of the sensor with the signal frequency 1.5 MHz. The sensor circuit has been completed. Finally, we conducted a test on the static characteristics of the magnetic sensors. The test turned out that the sensor has eminent properties such as excellent linearity, high sensitivity, no hysterics phenomenon and good repeatability, within a certain magnetic field.