Laser polishing of titanium surfaces obtained by additive manufacturing process

Institut de Recherche en Génie Civil et Mécanique UMR CNRS 6183, Centrale Nantes, Nantes, France

^* benoit.rosa@ec-nantes.fr

Abstract

Additive Manufacturing (AM) surfaces are composed by different textures and high roughness values which tend to limit its functionalities. Laser polishing process is enabling to smooth surfaces by material melting, change surface texture and decrease surface roughness (S_a). Based on a five axes machine, which consist of milling and Laser Metal Deposition (LMD) processes, the machine is additionally integrating laser polishing process on the same architecture. This paper aims at study laser polishing of laser metal deposition of titanium surfaces. LMD of titanium surfaces are composed by chaotic texture directly induced by the physical phenomenon of the process in use. Laser polishing process (LP) has an impact on the final surface regarding a multi-scale approach. The determined operating parameters and path strategy of laser polishing process decreases surface roughness by 78% and allow smoothing the initial chaotic texture. A polished surface roughness of 6.01 μm was obtained from an initial of 27.6μm.