Effects of Fabrication Parameters on the Properties of Parts Manufactured with Selective Laser Sintering: Application on Cement-Filled PA12

Abstract

Selective laser sintering (SLS) becomes a promising technology for manufacturing complicated objects with small to moderate numbers from a wide range of polymeric and metallic powders. However, the fabrication parameters in the SLS process need to be tailored for each end-use fabricated product. Hence, it becomes extremely important to investigate the effects of fabrication parameters on the mechanical and morphological properties of SLS parts. For this purpose, the present experimental work is devoted to evaluating the effects of some important fabrication parameters, that have not received proper attention in the published literature, on the properties of cement-filled polyamide 12 (PA12) parts manufactured with the SLS technique. The effect of scanning vector length on the tensile, compressive, and flexural strength of manufactured PA12/white cement parts is investigated. Also, the end-of-vector (EOV) effect on the edge geometry of manufactured parts is studied. Moreover, the effect of incident laser power (LP) on the surface quality of fabricated SLS PA12/white cement parts is qualitatively evaluated. The results from this work revealed that the scanning vector length significantly affects the mechanical properties of SLS parts provided that the load is applied along the scanning vector direction. Also, it is noticed that excessive exposure to laser energy at layer edges can deteriorate the part’s edge and in some cases can cause localized heating and burning of the part’s edge and, eventually, can result in surface microcracks. Finally, the experiments confirmed that increasing the laser power can enhance the surface roughness of manufactured parts; however, excessive increase in laser power causes localized burning and initiation of surface microcracks.