Model for the Yield Stress of Magnetorheological Fluids
Si Hu(1),Peng Xianghe(2),Chen Weimin(2)
(1 Key Lab. for the Exploitation of Southwestern Resource & the Environmental Disaster Control Engineering)
(2 Institute of Intelligent Materials and Structures, Chongqing University Chongqing, 400044)

Abstract: The magnitude of the yield stress of magnetorheological fluids is impo rtant for engineering applications. Based on the magnetomechanics, the microstru cture of chains consisting of polarized particles, and the interaction between p articles, the shear stress distribution contributed by a single chain of polarized particles is formulated, and then the yield stress of magnetorheological fluids is obtained under the assumption that the distribution of chains tends normally. The effects of the applied magnetic field intensity, the size of the particles, and the volume fraction of the particles on the macroscopic yield stress are analyzed. The proposed model is capable of analyzing the effects of other influ encing factors on the yield criterion of MRFs, which may assist the design and development of high-performance MRFs.
Keywords: magnetorheological fluids, magnetorheological effect, shear stress, shear strain rate.