| Barium ferrite is widely used in permanent magnet, magnetic recording and stealth material etc. In order to obtain good properties, the particles of barium ferrite tend to micronization. The agglomeration becomes one of the main problems which limit the application of barium ferrite. In this thesis, the dispersion behavior of barium ferrite and molding of anisotropy barium ferrite in magnetic field were studied. The results of the study are as follows:1. The interaction of barium ferrite particle in the liquid was calculated. The result indicates that the force of Van der Waals and magnetism attraction between the particles were the most reason, which result in agglomeration of the barium ferrite particles in the liquid. The magnetism attraction was the main factor that causes the particle agglomeration when the barium ferrite particle is more that 0.5μm.2. Electrostatic dispersion of barium ferrite particles in the air was discussed. The square of the charging field intensity is inversely proportional to the critical radius of barium ferrite particle.3. The effects of dispersants and other parameters on the dispersion in the liquid were examined. The results show that the dispersion of the particle barium ferrite will get better with the increase of ball-milling time and tend to be stabilization after slurry was milled for 16h. The sodium dodecyl sulfate and polyethylene glycol compound dispersant is the best. PH value also has effect on the dispersion, when slurry at pH 10, the dispersion was improved. The analysis of XRD suggested that the dispersants will not result in the change of the component of the barium ferrite.4. Molding of anisotropy barium ferrite in magnetic field was investigated. The effect of dispersion, intensity of magnetic field and temperature of sinter were discussed. The results showed that the anisotropy of barium ferrite will be better while adding dispersant in the slurry and will gain excellent anisotropy barium ferrite when...
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