Preparation And Properties Study Of Magnetic Fluid

Magnetic fluid is a colloidal suspension of single-domain magnetic particles, with typical di-mensions of about 10nm, dispersed in a liquid carrier. The liquid carrier can be polar or nonpolar. We review the main properties and some applications of Magnetic fluid in this paper. We consider the stability of Magnetic fluid in terms of various force on the magnetic particles.In this paper ,firstly ,we synthesize Fe3O4 nanoparticle through the coprecipitation of Fe3+ and Fe2+ in aqueous alkali, and then coated Fe3O4 nanoparticle with acid, lastly dispersed Fe3O4 nanop-article in kerosene, and this is magnetic fluid. The surface chemistry and the micro morphology, th-e phase composition , crystal structure and magnetic hystersis loop of as prepared samples were an-alyzed by means of scanning electron microscope (SEM), X-ray diffraction(XRD), vibrating samp-le magnetometer( VSM), respectively. Through the results of experimenrt, we know that the mean size of Fe3O4 nanoparticle is about 14nm, and the magnetic particle is superparamag-netism.The magnetic particle would agglomerate into magnetic chains along the magnetic field, whi-ch results in the anisotropy in magnetic fluid. we transported magnetic fluid into the glasses to form magnetic fluid film. The magnetic fluids show birefringence and dichroism under a magnetic field. We study the factor which may influence the birefringence and dichroism of magnetic fluid, findi-ng that the concentration of fluid, strength of magnetic field and included angle could infect the op-tical properties of magnetic fluid.Systematical studies of the relaxation time upon application of the on-off magnetic field with varied experimental parameters indicate that the switch response time depends strongly on the stre-ngth of the magnetic field and the concentration of the magnetic nanoparticles in the fluid. Our sys-tematical studies of the on-off switch times upon application of the on-off magnetic field under var-ied experimental conditions indicate that the relaxation time depends on the experimental paramet- errrrs such as the strength of the magnetic field, the concentration of the magnetic nanop-articles in the fluid, and the polarization direction of the incident light. Magnetic fluid has potential applica-tions in the construction of various functional devices because of its magneto-optical effects.