Laser-assisted post-processing of additive manufactured metallic parts

Laser-assisted additive manufacturing (AM) is the process of successively melting thin layers of material using a laser source to produce a three dimensional device or product. From the many technologies available, only a few can produce metallic parts that fulfil the requirements of industrial applications. Ultrafast laser machining is a new and promising technical approach for post-processing AM parts since laser ablation and surface modification processes could be applied with high accuracy for trimming shape and functionality, i.e., edge quality and wettability. The impact of different ultrafast laser parameters is evaluated for AM samples, which are examined for surface roughness before and after the laser-assisted post-processes. For all the parameters tested, the use of ultrafast laser resulted in a homogeneous material ablation of the samples’ surfaces. For the investigated parameter range, the AM building tracks were still maintained even after ultrafast laser post-processing. The achieved results showed the formation of self-organized porous structures at low laser scan velocities leading to an enhanced surface roughness. For higher scan velocities characteristic nano ripples might be induced having no significant impact on the measured surface roughness.