Study On The Fabrication Process Of18Ni300Maraging Steel By Selective Laser Melting And The Experimental Analysis On Laser Melting Of Metal Powders

Selective Laser Melting (SLM) is one of the important methods ofrapid prototyping process. SLM fabricates the metallic parts by melting themetal powder layer by layer. Because of its various advantages, manystudies on the optimization of the SLM process for different materials havebeen carried out, which is very important for the industry. This thesis hastwo main parts:Firstly, the SLM fabrication of18Ni300maraging steel has beenstudied on a reconstructed Phenix PM250machine. The research startswith the SLM process from the single lines to a solid part. The influence ofthe process parameters on the fabrication process, such as the laser power,scanning speed, thickness of powder bed, scanning strategy etc, on thequality of fabrication was studied. The parameters for the solid parts wereoptimized and the metallic parts with geometry complex are successfullyfabricated.Secondly, the experimental analysis on the laser melting the powderswas been carried out on the instrument installed with a high-speed camerasystem. The phenomenon of melting the Ti-, Ni-, Fe-and CoCr-basedalloys under different SLM parameters was recorded and analyzed. Themelting process of the powders including the movement of powder particleand the gas flow was discussed.