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Silicon carbide ceramics have excellent characteristics of density, thermal expansion coefficient, good wear resistance, high hardness, good thermal stability, high temperature strength, thermal conductivity and thermal shock, and a wide range of application areas, and prospects. However, the characteristics of having a high strength, high hardness, etc. to its molding, machining brought great difficulties. And selective laser sintering technology can be directly based on the CAD model of the entity, prototypes or parts forming a complex shape. The use of selective laser sintering forming silicon carbide parts development prospects abroad at the preliminary study stage, the country has not reported. The purpose of this paper is to study the selective laser sintering silicon carbide forming process, the main contents and conclusions are as follows: the selective laser sintered silicon carbide ceramic preform study. Analysis of silicon carbide ceramic indirect selective laser sintering principle and characteristics, explore CO 2 and YAG lasers indirectly forming of silicon carbide mechanism and the difference between, the several binders formability, and selective laser forming silicon carbide powder forming process parameters: preheating temperature, laser power and scanning rate optimization, as well as considering other factors to determine the optimum forming parameters: -280 purpose silicon carbide powder, binder for epoxy Resin E06, to determine minimum binder content of 2wt%, the continuous CO 2 laser, and the preheating temperature was 40 ° C, the laser power of 15W, the scanning speed of 2000mm / s, the scan pitch 0.1mm single layers thick 0.1mm. Epoxy protection of the atmosphere and the air in the pyrolysis behavior, and to determine the selective laser sintering silicon carbide shaped billet vacuum degreasing process and oxidation degreasing process; pyrolysis behavior and high-temperature sintering of silicon carbide defatted study, 54.9% porosity after degreasing calcined. Porous silicon carbide parts impregnating epoxy E-42 and Novolac type phenolic resin polymer matrix composites, three-point bending strength 65.3Mpa; explore the use of selective laser sintering and direct metal oxidation technology combined The process of Direct Preparation of a complex shape having a high dimensional accuracy of the ceramic matrix composite material parts, the ceramic phase and metal phase into a three-dimensional network-shaped distribution, the volume fraction of each phase: SiC, 45.1%, Al, 2 O 3 32.7%, residual metal phase was 18.0%, and 4.2% of the porosity of the three-point bending strength 361.2MPa. More systematic study of silicon carbide SLS molding process and post-process, selective laser sintering can be used for forming silicon carbide composite parts. This is a useful exploration of the future of the selective laser sintering process to introduce a comprehensive field of ceramic materials and composites forming.
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