Preparation and study of model magnetorheological fluids

Purpose: The aim of this work was preparation of the model magnetorheological (MR) fluids. Basic properties of prepared MR fluids, as their response to an external magnetic field and their stability, were investigated. Moreover (furthermore) few results concerning stabilizing effect of various additives are presented. Design/methodology/approach: Model MR fluid was prepared using three type of carriers: silicone oil OKS 1050, synthetic oil OKS 352, mineral oil OKS 600 mixed with carbonyl iron powder CI HQ. Furthermore, to reduce sedimentation Aerosil 200 and 972, Arsil 1100 and Arabic gum were added as stabilizers. MR effect was measured using device working as Couette’s viscosimeter equipped with coil generating magnetic field. Sedimentation was measured by simply observation of changes in boundary position between clear and turbid part of MR fluid placed into glass tube. Findings: Influence of the additives presence on the MR effect was determined. The presence of additives did not diminish the magnetic effect but even increased the dynamic viscosity in existence of an external magnetic field. The stability of MR fluid was improved by adding additives to the formulation. Moreover, increasing stabilizer concentration further enhanced the MR fluid stability. The best result was achieved in case of Aerosil 9782 at 2 % content. Research limitations/implications: MR fluids with excellent properties can be applied in various fields of civil and safety engineering, transportation and life science. However, due to sedimentation, MR fluid response to magnetic field is restricted and in an extreme situation could lead to the fail that is why further efforts must be still made in order to obtain even better results. Originality/value: This article provides set of new data about improvement of MR fluid stability in the presence of selected stabilizers and contains few remarks how the formulation of MR fluid affect its properties.