Review of magnetorheological fluids application in mechanical systems

Magnetorheological fluids (MR fluids) are suspensions of micron-sized, magnetically-polarizable particles in oil or other liquid. The essential characteristic of these fluids is their ability to reversibly change from a free-flowing, linear, viscous liquid to a semi-solid with controllable yield strength in milliseconds when exposed to a magnetic field. This paper will review the basic principles of MR fluids and the ways in which they are engineered into mechanical devices and systems. A variety of specific application examples, including MR dampers, MR brakes and MR clutch will be described.