Among all additive manufacturing processes, Directed Energy Deposition-Arc (DED-Arc) shows significantly shorter production times and is particularly suitable for large-volume components of simple to medium complexity. To exploit the full potential of this process, the microstructural, mechanical and corrosion behavior have to be studied. High stickout distances lead to a large offset, which leads to an instable electric arc and thus defects such as lack of fusion. Since corrosion preferentially occurs at such defects, the main objective of this work is to investigate the influence of the stickout distance on the corrosion behavior and microstructure of stainless steel manufactured by DED-Arc. Within the heterogenous structure of the manufactured samples lack of fusion defects were detected. The quantity of such defects was reduced by applying a shorter stickout distance. The corrosion behavior of the additively manufactured specimens was investigated by means of potentiodynamic polarization measurements. The semi-logarithmic current density potential curves showed a similar course and thus similar corrosion resistance like that of the conventionally forged sample. The polarization curve of the reference material shows numerous current peaks, both in the anodic and cathodic regions. This metastable behavior is induced by the presence of manganese sulfides. On the sample surface a local attack by pitting corrosion was identified.

Abstract Laser-based powder bed fusion of metals (PBF-LB/M) is found to be a promising processing method for the fabrication of components with no limits of complexity by adding layers upon layers of material. However, drawbacks such as pro- ductivity and dimension limitations adversely affect the employment of com- ponents processed by additive manufacturing (AM) in envisaged applications. This brings welding and joining techniques into play to integrate AM metal parts into larger assemblies. In the present study, electron beam welding is used to join the AlSi10Mg specimens, fabricated via two different manufacturing processes, that is, PBF-LB/M and casting. The main focus is to study the quasistatic and fatigue behavior of similar and dissimilar welded joints in different combinations, namely AM–AM, AM–cast, and cast–cast, alongside thorough microstructure analysis, to investigate the correlation between the microscopic and macroscopic properties. Dissimilar welded joints demonstrate inferior material strength. This fact can be attributed to the inherent coarse microstructure of the cast material. Although similar welded joints of AM components suffer from high porosity in the weld zone, they are characterized by a better fatigue life, which can be attributed to the equiaxed eutectic microstructure in the welded area.