Surface Texture Anatomy of Additive Manufacturing Components: Towards the Perfect Surface Finishing (Post-Processing)

In the past years, we have experienced a growing demand for additive manufactured (AM) components in the aerospace industry. AM is a viable option to produce unique components with a wide range of possible shapes.  Furthermore, the AM process is capable of producing components structure with reduced weight, without compromising its structural strength.  However, AM produced components have an intrinsic problem—their surfaces are extremely rough and packed with multiple layers of partially melted/sintered powder and significant defects. In order to be approved for aerospace applications, AM-built parts need to be surface finished to remove their “as-produced” surface roughness and meet the needs of the industry. AM as-produced surfaces are filled with partially melted/sintered powder and under certain operation, conditions can be considered as potential foreign object debris (FOD). There is a clear need for new surface finishing (post-processing) techniques capable of not only improving the appearance of the AM produced components, but also that are capable of removing all these surface defects and improving the mechanical strength of the components. In order to address this need, REM Surface Engineering is developing a new AM program based on their already existing technology ISF® (isotropic superfinishing) process. The ISF® process is a chemically accelerated vibratory finishing process that can be utilized to overcome the challenges to produce surface-finished components that meet the standards of the industry. We will present our recent achievements on components made of different alloys by EBM or SLM. So far the process has been shown to improve the surface of complex components, removing the partially melted/sintered metal particles from the surface, and improving bending fatigue and tensile strength. Moreover, we will also discuss the best methods for the characterization of these surfaces using surface texture parameters that correlate accordingly with the dynamic mechanical performance of the components.