Christopher Lefky1 Owen Hildreth1

1, Arizona State University, Tempe, Arizona, United States

Support structures are included in most 3D printing techniques, such as directed energy deposition (DED) and powder-bed fusion (PBF), in order to alleviate thermal stresses and allow for the printing of overhanging parts. Recently, dissolvable metal supports have been introduced as a solution to reduce the costs and time associated with production. Following PBF fabrication, parts were surrounded in a carburizing paste that introduced chromium carbides over the initial ~100 µm of surface, reducing the free chromium concentration. This sensitization makes the carburized regions very susceptible to corrosion in a solution of nitric acid and potassium chloride. Since sacrificial supports are typically <200 µm in width, they are easily dissolved during the process. This work will study the effect of processing parameters and microstructure evolution throughout the dissolution process. Specifically, discussing how the microstructure affects dissolution and the resultant microstructure after support removal is complete. Processing parameters such as potential will be varied to target different phases during dissolution.