On the effect of spatter particles distribution on the quality of Hastelloy X parts made by laser powder-bed fusion additive manufacturing

Laser Powder-bed Fusion (LPBF) is considered to be one of the main additive manufacturing (AM) methods for the production of functional metallic parts. Despite its numerous advantages, the spatter formation and distribution on the powder-bed surface, due to the melt pool instability and flow field around the process zone, is considered as one of the drawbacks of this process. In this study, a comparison has been performed on the virgin and spatter powder particles. Chemical composition, phases, microstructure, morphology and thermal behavior of virgin and spatter Hastelloy X (HX) powders have been studied to assess their contributions to the part quality. Moreover, the interaction of the spatter particles with the shielding gas and the recoater motion has been analyzed to determine the distribution and effect of spatter particles on the quality of LPBF-made parts at different locations in the build plate. In this regard, surface roughness was measured on various surfaces of the parts. It was found that the top surface roughness is increased from 14.4 mu m to 28 mu m in the spatter rich region of the build plate, thus this region is recommended to be avoided for the manufacture of high quality parts.