Abstract: Additive manufacturing (AM) methods have garnered considerable attention owing to their flexibility in fabricating complex parts with desirable mechanical properties. However, the poor surface quality of the resulting metal parts remains a severe challenge for the applications. Here, a novel dual-additive synergy strategy is presented, which simultaneously enhances material removal efficiency and regulates electrode surface reactions during electrochemical polishing (ECP) of AM AlSi10Mg. Theoretical studies and experimental characterizations confirm that NaF promotes selective dissolution at the peaks, while glucose acts as a stabilizer for the surface valleys. This approach effectively facilitates the selective removal of surface protrusions, achieving a smoother and more uniform surface finish, resulting in a surface roughness reduction of approximately 86 %, compared to a 63 % reduction without additives. This study not only provides a new approach for optimizing surface quality of AM AlSi10Mg but also offers new insights into electrolyte design and the stabilization of metal anodes.

Key words: Additive manufacturing, Electrochemical polishing, Interface reaction, AlSi10Mg, Surface finishing