Enhancing surface uniformity and edge fidelity in plasma electrolytic polishing via vibration-assisted bubble control

To enhance surface uniformity and mitigate edge rounding in plasma electrolytic polishing (PEP), this study proposes a vibration-assisted plasma electrolytic polishing (V-PEP) approach. Finite element simulations were employed to elucidate the mechanisms through which workpiece vibration influences bubble evolution and electrolyte flow behavior during the polishing process. Experimental results confirm that vibration assistance significantly improves polishing performance under a range of voltage conditions. The effects of vibration frequency and amplitude on surface quality were systematically investigated, followed by a comprehensive evaluation of surface integrity. Compared with conventional PEP, the V-PEP process increases the surface roughness reduction rate by 25.16%, decreases the edge rounding diameter by 39.89%, and enhances the material removal rate by 47.32%. Moreover, vibration assistance does not compromise surface integrity. The induced vibration promotes the forced detachment and uniform dispersion of bubbles, thereby ensuring homogeneous material removal and effectively suppressing edge rounding. The proposed method was further applied to polish laser powder bed fusion (LPBF) additively manufactured sample with micro-groove structures. These findings contribute to maintaining the geometrical fidelity of workpieces and advancing the application of PEP technology in the precision finishing of complex geometries.