Machining performance study in Radial Ultrasonic-Assisted Rolling Electrochemical Micromachining

Abstract

Surface texturing is an attractive approach for improving the friction, tribological and heat transfer performance in the equipment. Ultrasonically assisted electrochemical micromachining (USEMM) is a promising method for generating micro dimples as it can reduce the overcutting and enhance electrolyte renewal to improve the machining localization and increase the material removal. Considering the micro dimple array fabrication on smooth and rotary workpiece, the radial ultrasonic rolling electrochemical micromachining (RUREMM) is presented in this paper. With the cathode revolving and ultrasonic vibration in the interelectrode gap, the electrolyte renewal and the machining stability improves, micro dimples array with good performance could be obtained. Detailed discussions were done based on the machined micro dimples on 304 stainless steel plate at different conditions. Results show that the machining efficiency of micro dimple in RUREMM is better than in (electrochemical micromachining) EMM and the existing ultrasonic vibration in the interelectrode gap is more effective to enhance the machining performance. Then, effects of gap pressure on the material removal rate, machining accuracy and roughness are studied and discussed in detail. Experiments denote that the width of the micro dimples is decreased by 14.6%, the depth of the micro dimples is increased by 19.2%, the cross-sectional area is expanded by 31.2 %, the roughness of the bottom is decreased by 23.9% and better surface quality for the side wall could be obtained by using the selected parameters, 10 % NaNO3, 50 μm machining gap, 0.8 r/min rotation speed, 28 kHz Ultrasonic vibration frequency, 10μm amplitude in RUREMM.