Investigation of the properties of selected magnetorheological fluids

Abstract

The paper presents the results of research on the rheological properties of magnetorheological (MR) fluids with different physical and chemical compositions. The research concerned complete compositions of MR fluids as well as base fluids (samples containing no particles with ferromagnetic properties). Magnetorheological fluids consisted mainly of a carrier liquid in the form of glycerin or OKS 352 silicone oil, with magnetite or iron pentacarbonyl particles. The paper demonstrates the effect of the selection of individual components of the MR fluids on their rheological properties, paying attention to the interaction of the base liquid with the particles of the solid phase of the MR fluid. Under the conditions of exposure to a magnetic field, the type of ferromagnetic particles (their magnetic properties) have a decisive impact on the magnetorheological response of the fluid (change in rheological properties due to the effect of the magnetic field on the fluid). The magnetite-based samples showed a tangential stress of 1000 Pa, while the use of iron carbonyl allowed to obtain approximately 8000 Pa (with respect to the case where B = 500 mT, $\stackrel{•}{\gamma }=100s^{-1}$ ). No significant differences in rheological properties were recorded between the oleic acid- and silica-stabilized samples.