Thixotropic Magnetorheological Fluid for Controlled Vibration Mounts

The article is devoted to the development of the composition of a thixotropic magnetorheological fluid and a laboratory setup for determining the properties and characteristics of magnetorheological fluids. The magnetorheological fluid was developed on the basis of copolymers of methyl methacrylate and n-butyl methacrylate, a mixture of diethylbenzenes, dioctylphthalate, oleic acid, and carbonyl iron of the P-10 grade. To impart thixotropic properties to the magnetorheological fluid, a 1% solution of modified urea is added. For the study of magnetorheological materials, a laboratory setup was developed that allows one to measure the yield stress, plastic viscosity, flow curves, magnetorheological characteristics and the magnetization curve. The setup includes two hydraulically connected cylindrical vessels and one external cylindrical vessel filled with the investigated magnetorheological fluid between two poles of a powerful magnet. The shear stress is determined through the magnitude of the viscous friction force that occurs when a load immersed in the liquid is evenly lifted, and the strength and induction of the magnetic field are determined by means of two Hall sensors.