Improving the quality of up-facing inclined surfaces in laser powder bed fusion of metals using a dual laser setup

Abstract

Surface quality of parts produced by laser powder bed fusion (LPBF) is often insufficient for their final application. Up-facing inclined surfaces are among the major challenges, due to the combination of elevated edges (edge effect) and the staircase effect. This work presents a novel methodology to enhance the quality of inclined surfaces using a dual laser PBF setup. In the first step called “selective powder removal”, powder is blown away from undesired areas using shock waves produced by a nanosecond pulsed wave laser. Consequently, the newly exposed inclined surfaces can be remelted with a continuous wave laser, reducing significantly the surface texture.