Additive manufacturing (AM) metal components have an intrinsic rich surface texture, characterized by an extremely rough surface and near-surface defects. These surface-related defects (SRD) will have detrimental effects in the fatigue performance and corrosion resistance of the components. Most of the SRD are associated with porosity trapped between the contour and hatching pass during the building process. Consequently, just a surface finishing operation will not be able to improve the surface texture by uncovering these near-surface pores. Nevertheless, there is a clear need for surface finishing, not only improving the appearance of produced AM components but also removing all SRD, improving the mechanical and corrosion resistance properties of the components. However, surface finishing of AM components is a very difficult task due to the extreme complexity that free-form construction technology offers to the industry. In addition, AM-built components have very delicate features, extensive internal structures and different types of surface textures within the same components (upskin, downskin, etc.). Additionally, the extent of the SRD drops to 200 microns below the surface, requiring considerable metal removal. This makes it very difficult to eliminate uniform metals during the surface finish. Combining the surface finishing process after specific heat treatments capable to heal the porosity, while keeping the metallographic structure of the built specimens intact, should produce a component with remarkable surface finishing, without the need of an extended surface material removal. In addition, the use of the contour pass might be also modified to optimize for these combinatory post-processing operations.
- Understand the implication of AM surface texture on mechanical performance and corrosion performance.
- Understand the importance of HIP combined with surface finishing on mechanical performance and corrosion performance.
- Understand how printing parameters have an effect on the post-processing methods, and how to optimize for those methods.