Review-Electropolishing of Additive Manufactured Metal Parts

Most metal AM technologies are rapidly approaching, and in some cases even exceeding the Technology Readiness Level 8, indicating that they are widely available and capable of completing a wide range of projects despite identified process restrictions. Thanks to significant technological progress made in the last decade, more industries are incorporating metal additive manufacturing in their production process to obtain highly customized parts with complex geometries. However, the poor surface finish of AM parts is a major drawback to their aesthetics and functionality. Over the years, different approaches were proposed to enhance their surface quality, each bearing its limitations. Among the proposed technologies, electropolishing is a strong candidate for improving the surface finish of AM parts. This study aims to review the literature on electropolishing of AM parts. However, to provide a comprehensive study of the different aspects involved, a brief review is also presented on the origin and consequences of the surface properties of AM parts as well as an evaluation of other available post-treatment technologies. Finally, the existing challenges on the way and potential countermeasures to expedite the industrial application of the electropolishing process for post-treatment of AM parts as well as future research avenues are discussed.