Research on rheological properties and phenomenological theory-based constitutive model of magnetorheological shear thickening fluids

Abstract This paper investigates the rheological properties of magnetorheological shear thickening fluid (MRSTF) and proposes a phenomenological theory-based constitutive model. Multiple samples with varying mass fractions and particle sizes were prepared. Then, the rheological properties were experimentally studied, including the effects of silicon particle size and concentration, carbonyl iron powder concentration and magnetic field on rheological properties. Next, the sedimentation stability experiment was also carried out by the static observation method. Finally, based on phenomenological theory, a constitutive model called the M-S model was derived through geometric transformation of shear stress curves. The results show that there is an inhibitory relationship between magnetorheological and shear thickening effect, and the correlation between composition and rheological properties was established, which can provide guidance for preparation of MRSTF with required properties. It also shows that the MRSTF under specific preparation scheme could effectively avoid sedimentation, and its performance is clearly superior to traditional materials in terms of sedimentation resistance and damping adjustment. The accuracy and universality of the proposed model are fully verified by fitting shear stress curves and calculating the goodness of fit values. All these investigations can offer an effective guidance for further study of MRSTF in controllable damping equipment development.