Hydrodynamic Properties of Fe3O4 Kerosene-Based Ferrofluids with Narrow Particle Size Distribution
ZHANG Jian-Hui1,2, XU Xue-Fei1, SI Ming-Su1, ZHOU You-He1, XUE De-Sheng1
1Key laboratory for Magnetism and Magnetic Materials of Ministry of Education, Lanzhou University, Lanzhou 730000
2School of Mechatronic Engineering, Lanzhou Jiaotong University, Lanzhou 730070
Hydrodynamic Properties of Fe3O4 Kerosene-Based Ferrofluids with Narrow Particle Size Distribution
1Key laboratory for Magnetism and Magnetic Materials of Ministry of Education, Lanzhou University, Lanzhou 730000
2School of Mechatronic Engineering, Lanzhou Jiaotong University, Lanzhou 730070
Abstract： We investigate the hydrodynamic properties of Fe3O4 kerosene-based ferrofluids with narrow particle size distribution. The ferrofluids are synthesized by improving chemical coprecipitation technique. A narrow distribution of 8.6--10.8nm particle sizes is obtained from the magnetization curve with the free-form model based on the Bayesian inference theory. The fitting result is consistent with average particle size obtained from x-ray diffraction. With the increase of applied magnetic field and magnetic particle concentration, apparent viscosity of ferrofluids increases. At concentration 4.04%, the type of flow for the ferrofluid transforms from Newtonian to Bingham plastic fluid as the applied magnetic field increases.
2005, Vol. 22 
