1 State Key Laboratory of Material Processing and Die & Mould Technology, School of Material Science and Engineering, Huazhong University of Science and Technology 2 Research Institute of Huazhong University of Science and Technology in Shenzhen, 3 School of Material Science and Engineering, Wuhan University of Technology, Wuhan 430070, China 4 Shanghai Aerospace Equipment Manufacturer, Shanghai 200245, China
Compared with traditional technologies, 3D printing technology has shown great advantages in direct formation of metal and polymer parts with complex shapes. However, there are many problems in the preparation of ceramic parts via 3D printing. In this respect, lots of researches have been done by Prof. Shi Yu-Sheng’s group in Huazhong University of Science and Technology on the preparation of different ceramic materials used for 3D printing technology and related forming methods. In this review, two main methods to prepare composite powders used in Selective Laser Sintering (SLS) were detailed introduced: (1) mechanical mixing method, by which ceramic powders and polymer were directly mixed; (2) dissolution-precipitation process or solvent evaporation method, by which the ceramic powders were coated with polymer. The results showed that both two preparation methods mentioned above were suitable to prepare ceramic-polymer composite powders with good fluidity for 3D printing technology. Furthermore, the forming mechanisms of SLS and the effects of SLS process parameters, including preheating temperature, laser power, layer thickness and so on, on mechanical properties and manufacturing accuracy of ceramic green parts were systematically discussed. On the basis of above results, porous cordierite and kaolin ceramics with three dimensional pore structures, which were difficult to be fabricated by the conventional forming technologies, were manufactured by SLS technology with optimized process parameters. In addition, to improve the density and mechanical properties of SLSed ceramic parts, a hybrid technology named SLS/Cold Isostatic Pressing (CIP) was proposed by introducing the CIP technology into the field of SLS, and dense Al2O3, ZrO2 and SiC ceramic parts with high performance and complex structure were prepared through this hybrid technology. The results indicated that SLS and SLS/CIP technologies could be the promising routes to prepare high-performance ceramic components used in the fields of aerospace, national defense, etc.