ER PROPERTIES AND FLOW-INDUCED MICROSTRUCTURES OF AN ER FLUID BETWEEN TWO PARALLEL DISK ELECTRODES IN SQUEEZE FLOW MODE

Abstract

When an electrorheological fluid between two parallel disk electrodes is subjected to squeeze mode excitation, the microstructural flow behavior of the ER fluid has been investigated in close relation to the measured electrorheological properties. A dilute anhydrous ER fluid made of 10 vol% carbonaceous particles dispersed in silicone oil and two ITO glass disk electrodes are used to visualize the microstructural flow behavior. The squeeze tests are carried out on a mechanical testing machine in tensile, compression and oscillatory squeeze modes. The ER properties and the associated flow-induced microstructures are measured and visualized for different initial DC electric field strengths and initial gap hi = 0.5 mm between the electrodes in two different configurations: (a) the fluid is placed only between the electrodes (conf-1) and (b) the two electrodes are immersed in the ERF (conf-2).