Electrorheology is the investigation of the rheological behavior of fluids containing electrically active particles. These electrorheological fluids (ERF) reversibly change their consistency in response to an electric field. They are primarily used for dampers, clutches, and brakes that need to react very quickly. Another field of use is the flow control of active hydraulic valves. A rheometer with an Electro-Rheological Device (ERD) is used to apply an electric voltage up to 12.5 kV DC (AC is possible as well) within a temperature range of -40 °C to 200 °C.
Watch this 5-minute course to find out more about electrorheology.