Material Removal and Surface Modification of Copper under Ultrasonic-Assisted Electrochemical Polishing

Electrochemical polishing exhibits high efficiency and simplicity of operation and presents broad prospects in metal field processing. However, the poor conductivity of the surface oxides generated during electrochemical polishing may lead to uneven electrolysis and surface protrusions if not promptly removed. This study combined ultrasonic treatment with electrochemical polishing and adjusted the angle of the ultrasonic jet to investigate the effect of ultrasonic-assisted electrochemical polishing on the removal of protruding microstructures. The study examined the surface morphology, hardness, residual stress, and workpiece contact angle before and after processing. The results demonstrated that ultrasonic assistance can effectively promote electrochemical reactions and improve the removal efficiency of the workpiece surface. With an increase in ultrasonic power and processing time, the corrosion potential of the workpiece decreased, which accelerated the material removal rate. The roughness of the workpiece surface increased within the threshold. Additionally, the surface hardness increased to 105.3 HV, the residual stress was enhanced by 517.89 MPa, and the contact angle increased to 104.7°. The erosion characteristics and hydrophobicity of the workpiece were also enhanced.