Laser powder bed fusion (PBF-LB/M) is used in various industries to manufacture complex parts with high precision. For most applications, a low surface roughness of less than 1 µm is required. This is a major challenge for additively manufactured (AM) parts and results in a cost and time intensive post-processing. The high surface roughness and their resulting residual porosity influence the mechanical properties, especially dynamic ones [1-2]. Post-processing methods like polishing and machining have been employed to improve fatigue life, but their effectiveness is limited [3]. This work presents aluminium pack cementation as a method to reduce surface roughness and improve fatigue resistance of AM parts. 
The effect of the pack cementation process on the resulting microstructure in the surface zone of PBF-LB/M specimens was investigated. For this purpose, different Fe- and Ni-Basis alloys were investigated. The surface roughness of as-built and as-modified PBF-LB/M specimens was measured. Finally, the fatigue behaviour at room temperature and 400°C of both as-built and as-modified specimens will be presented.