The Study Of Levitation Object Of Magnetic Levitation Acclerometer

The superparamagnetism and designing methods of levitation objects of magnetic levitation accelerometer was studied in this paper. The study of this paper focused on the mechanism of superparamagnetism, magnetic force, and dispersion method of levitation object of magnetic levitation accelerometer. Firstly, this paper analyzed the mechanism of realized superparamagnetism, as well as the magnetization procedure and magnetic force of superparamagnetic levitation object of magnetic levitation accelerometer in external magnetic field. Secondly, different preparation methods of nanoparticles and properties of different polymer were compared. Thirdly, magnetite nanoparticles were prepared by chemical co-participation method and then dispersed into bismaleimide matrix via mechanical high shear method, according to the special required properties of levitation object. Finally, the prepared samples of levitation object were tested.The thesis was composed of six chapters, including three parts. Firstly, based on the reading of various materials, several kinds of levitation object of accelerometer were introduced and there defects were analyzed, as well as the situation of preparation of superparamagnetic composite using nano particles and polymer. Secondly, the thesis analyzed the mechanism of superparamagnetism of levitation objects of magnetic levitation accelerometer, studied the magnetization and magnetic force of levitation objects in external magnetic fields. In addition, the thesis analyzed the advantages and disadvantages of different methods for preparing magnetite nanoparticles and different kinds of polymer, studied the mechanism of nano magnetite dispersion. Finally, according to the specific requirement of levitation object of magnetic levitation accelerometer, superparamagnetic magnetite nanoparticles were prepared via chemical co-participation method. Bismaleimide, which have wide temperature range, excellent mechanic and isolation properties, was chose as matrix. Samples of superparamagnetic levitation object were prepared via dispersed magnetite nanoparticles into the bismaleimide matrix using mechanic high shear method. Test results of demonstrated that those self-prepared levitation object samples exhibited superparamagnetism and the magnetite nanoparticles were well dispersed. Those samples can be levitated by changing their magnetic force in external magnetic fields via adjusting magnetic field. Experiment results showed that the method for preparing superparamagnetic levitation object was valid.