| The communication technology, the computer technology and the sensor technology are the three supporting technology of information industry. The application area involves in electric machine control, industrial robot, medical electronics, automatic and so on. The frequently-used magnetic sensors contain fluxgate, hall sensor, huge magneto-resistor, piezomagnetic/piezoelectric sensor and so on. A composite magnetic sensor consisting of magnetic-film and tuning fork resonator is researched. This magnetic sensor has a higher Q value compared with a magnetic sensor structure consisting of magnetostrictive material, piezoelectric material and substrate. The compound position of film is analyzed using the Finite Element Analysis. The magnetic sensor structure is prepared by plastering magnetic-film with quartz tuning fork directly, and the experiment research is executed. The main work is as follows:①The physics feature and the oscillating mode of quartz tuning fork are investigated; the quartz tuning fork using in the magnetic sensor is researched. The species, the character, and the preparation of magnetic-film are investigated.②The finite element models of tuning fork is established by inputting geometric model, selecting element types, meshing solid model, applying loads and applying boundary conditions. The resonant mode of quartz tuning fork is analyzed, the compound position of magnetic-film is analyzed by finite element analysis, the most sensitivity compound position to resonant frequency change is got.③The magnetic-film/quartz tuning fork compound magnetic sensor is prepared, the experimental setup of the composite magnetic sensor is designed, the resonant frequency change and Q value change of device to magnetic sensor are tested. The sensitive structure analyzed by finite element analysis is compliance with the experiment. Experiment result indicates that the measured Q value is better than measured frequency, the high sensitivity of Q value can reach 119.471/mT, and the resolution of the magnetic field can reach 10-6 Tesla when the detection resolution of Q value detection is 1 and the Q value stability of tuning fork is 20ppm, the Q value is about 2000 at zero bias magnetic filed, has the character of high Q value. |
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