Surface layer porosity and surface quality in dependency of contour scanning strategy of Ti6Al4V parts

Abstract

Laser based powder bed fusion of metals (PBF-LB/M) grants the potential for the combination of modern design approaches like topology optimization with the production of near-net shape parts suitable for high performance application. But there is not only the need for high relative density of the parts but also a low surface layer porosity to achieve mechanical properties comparable or better than forging or casting. The surface layer porosity depends among other factors on scanning strategy, precisely the contour parameters, filler parameters and hatch offset. This work investigates the influence of the named parameters and energy input on the correlation of surface porosity and surface roughness of Ti6Al4V specimens. To correlate surface roughness and surface layer porosity with the used laser parameters micro computed tomography (µ-CT) measurements are used.