Selectively Laser Melting process (SLM) is an additive manufacturing (AM) process that constructs 3D structures with a high degree of freedom. AlSi10Mg is one of the currently used materials for SLM process, due to its mechanical properties, low shrinkage and melting point. Moreover, processing AlSi10Mg as AM enables lightweight structures which reduce energy consumption, and, thus, makes it attractive for many industries such as aerospace and automotive.

The microstructures of the SLM-printed AlSi10Mg alloy depend on the parameters and printed directions. In a previous study it has been found that corrosion attacks occur round and wide on the surface perpendicular to the printed direction (XZ). On the other hand, severely subsurface and deep undercut corrosion attacks were observed on surfaces parallel to the building platform (XY plane) [1]. This type of corrosion attack can compromise the structural stability of the component. Therefore, the appropriate surface treatment plays a crucial role for durability of the 3D component.

Plasma Electrolytic Oxidation (PEO) is an advanced electrolytic surface treatment for light metals such as aluminum, magnesium and titanium. This process produces an oxide ceramic-like layer, which is extremely hard but also ductile. These mechanical properties improve the corrosion and wear resistance significantly. The PEO structures and morphologies rely on substrate surface conditions, alloy elements, the microstructure and the process parameters. In order to find the superlative PEO surface for maximal protection on both printed planes, optimized PEO process is utmost required.

The goal of this study is to improve the corrosion and wear protection of 3D printed AlSi10Mg alloy by optimizing the PEO process. The corrosion behavior was investigated by using electrochemical impedance spectroscopy (EIS) as well as potentiodynamic polarization and long-term immersion tests. The wear behavior of the surfaces was examined by the Pin-On-Disc tribological test, while the morphologies of the resulting coatings were characterized by SEM/EDS. The results present the improvement of optimized PEO process by CERANOD®, which enhances the corrosion and wear protection on both printed planes successfully.