An Experimental Study of Downfacing Surfaces in Selective Laser Melting

This article presents an investigative study to evaluate the effect of process parameters on surface roughness and dimensional accuracy of downfacing surfaces. The material used in the study is Corrax steel and is fabricated using selective laser melting (SLM) technology. The fabrication process of the downfacing surface is different from the fabrication of the main or core region due to the poor thermal conductivity of loose powder particles beneath each layer. The processing parameters, namely, laser scanning speed, laser power, and layer reference, are investigated using a full factorial design of experiments method to discover their influence on surface roughness and dimensional deviation. Results show that the investigated factors are significantly affecting the quality of downfacing surfaces and controlling them will greatly influence achieving required surface properties.