Laser-based powder bed fusion of metals (PBF-LB/M) allows for intricate geometries and complex part designs, making it a key technology for advanced manufacturing. However, surface roughness is inevitable, affecting part properties such as mechanical strength, thermal performance, and wear resistance. While reducing roughness is often aimed for, some applications require specific surface textures rather than mere minimization. Existing research has explored roughness modification, but a comprehensive understanding of influencing factors is still lacking. This study introduces a holistic approach by statistically analyzing key process parameters to determine their impact on surface roughness characteristics.

The study examines how parameters such as laser power, scan speed, build platform position, and overhang angle influence roughness in Ti-6Al-4V components. By identifying relevant metrics, it lays the foundation for a systematic method to modify surface roughness in a controlled manner.

The results show that surface orientation relative to shielding gas flow influences the surface characteristics, with surfaces facing away experiencing lower surface roughness. Application of optimized downskin parameters also enables nearly identical roughness values on the up- and down-skin of 45° geometries. This leads to the possibility of constant surface roughness values independent of the surface orientation, which is especially advantageous in internal cooling channels. The findings contribute to a predictive analytical model for surface roughness control in PBF-LB/M.