Magnetic-responsive tension rheology behavior for grease-based magnetorheological suspensions

Abstract The tensile rheology behavior of grease-based magnetorheological (MR) suspensions at the presence of magnetic field was investigated by a magnetic-responsive tensile rheology model and the experiment in this research. The prediction for magnetic-responsive tension model corrected by the magnetic field-dependent attenuation coefficients is in accord with the experimental data under different magnetic field activation. Comparing with the thicker initial thickness of suspensions, the thinner initial thickness of suspensions at the application of same magnetic field induced larger tensile strength due to the stronger magnetic interaction between dipoles and the higher anti-deformation ability for the magnetic structures. Furthermore, the higher pull velocity promoted the formation of robust magnetic structures and activated the larger tensile rheological capacity for the grease-based MR suspensions along the direction of the magnetic field. Besides, the magnetic-structure tensile strength of MR suspensions inducing by the tensile traction of aluminum-created substrate material with the weak magnetic conductivity was much less than the tensile traction of steel-created substrate material with the strong magnetic conductivity. This study proposed a hypothesis where the difference between the magnetic-field attenuation rate and the magnetic-structure destruction rate leaded to the disagreement between the mechanical rheology model and experimental data at traction of the high tensile speed.