Machining Characteristics of Electrochemical Polishing Using Ultrasonic Vibration for Nanoscale High Surface Quality

This study demonstrates a method to improve the surface quality by adding artificial vibration to the electrolyte in electrochemical polishing (ECP, electropolishing). ECP is a typical non-contact surface polishing process that has been used to improve surface quality without leaving any of the mechanical scratch marks that can arise when applying mechanical processes. ECP can polish work material via electrochemical dissolution between the surfaces of an anode and a cathode, and irregular defects are generated on the surface by impurities and bubbles generated during machining. This study confirms that our novel ECP method yields improved results over conventional ECP based on experiments using vibration electrochemical polishing (VECP) with ultrasonic vibrations. VECP minimizes nanoscale surface defects, improves surface roughness, makes it possible to quickly remove materials at nanoscale by increasing the material removal rate (MRR). Under high current density, where the electrochemical relatively reaction is active, value of the current is increased when ultrasonic vibration is added. The localized roughness of the work material was measured by atomic force microscopy (AFM) according to various electrical conditions. In addition, we also compared the overall surface quality and productivity to those obtained by conventional ECP.