The Influence of the Temperature on the Dynamic Behaviors of Magnetorheological Gel

Magnetorheological (MR) gel is a new generation of MR material, which can overcome disadvantages attaching MR fluid such as sedimentation. MR gel is formed by the soft magnetic particle suspension in the gel-like matrix and its rheological properties are mainly controlled by the following two factors, i.e., magnetic field and temperature. Herein, MR gel based on polyurethane gel with a 60% weight fraction of carbonyl iron is prepared. The influence of temperature on the rheological characteristics of the MR gel sample is systematically investigated. Oscillatory shear test is used to investigate the impact of temperature on the modulus of the sample. It is observed that temperature has a significant effect on the viscoelastic properties of MR gel. The hysteresis responses activated by harmonic strain signal with frequencies of 0.1, 5, and 15 Hz and amplitude of 10% and 50% under five temperature levels are measured and employed to analyze the viscous and elastic properties of MR gel and the viscoelastic–plastic model is employed to capture the nonlinear hysteresis characteristics. From the analysis results, the viscoelastic–plastic model can predict the hysteresis properties of MR gel accuracy under various temperatures.