Abstract: The shear yield property of electrorheological (ER) polishing fluid was investigated for ER fluid-assisted polishing. The microstructure of fibrous columns formed by particles perpendicular to the electrodes was observed by electronic microscope when the electrical field was applied. A theoretical model for the static shear yield stress of the ER polishing fluid was built to calculate the shear strength of the chain structure of particles, which was based on the combination structure of ER particles with abrasive particles and the attraction forces between particles in ER polishing fluid. A series of experiments were conducted to measure the static shear yield stress of ER polishing fluid by the developed yield stress testing device. The effects of the species, sizes and concentrations of abrasive particles on the shear yield stress of ER polishing fluid were obtained and the validity of the presented model was confirmed by experiments.

Key words: mechanical manufacturing and automation, electrorheological polishing fluid, shear yield stress, electrical field intensity