Process parameters investigation for direct powder bed selective laser processing of silicon carbide parts

Direct-powder bed selective laser processing (D-PBSLP) is a promising technique for the manufacturing of complex-shaped parts of Silicon Carbide (SiC) ceramic. In this work, a complex optimization of the process parameters was performed by numerical and experimental analysis. The numerical model was used to determine and optimize the effect of laser power, scanning speed and hatching distance at different layer thicknesses of 20, 30 and 40 µm. Regarding the experimental process parameters study, powder compaction was also studied and optimized. The optimization parameter criteria were to achieve reproducible and high relative density parts. Concerning the experimental manufacturing process, D-PBSLP of alpha-silicon carbide parts with a maximum relative density of 81% were manufactured. Moreover, the process viability can be confirmed with the manufacturing of SiC complex shapes in absence of any additives in the initial powder and without or post-treatment. The results from this study could be used as a guide for process parameters selection.