Optimization of energy distribution over time for solid dielectric electrochemical polishing for additively manufactured parts

Metal additive manufacturing (MAM) processes inevitably result in high surface roughness due to factors such as the step and balling effects, especially on the side surfaces parallel to the build direction. This severely limits their applicability in precision applications. Therefore, surface post-processing of MAM components is critical. Solid dielectric electrochemical polishing (SDECP) is an eco-friendly method that effectively addresses the high initial surface roughness of MAM components. This study investigates the effect of different processing energy distributions on polishing performance by adjusting the electric pulse duty cycle during SDECP at a constant current. Energy distributions, including 50%, 70%, and 90% duty cycle pulses, as well as direct current (DC), are experimentally tested, yielding surface roughness reductions of 70.3%, 74.1%, 85.2%, and 85.0%, respectively. These experimental results, along with SEM images, reveal that larger duty cycles lead to better polishing performance, while DC pulses cause pitting corrosion. This study offers valuable insights into the efficient surface post-processing of MAM components.