Preparation of β-SiC by combustion synthesis in a large-scale reactor

PTFE

Preparation of β-SiC by combustion synthesis in a large-scale reactor
Yu-qiong Liu[1,2] Li-feng Zhang[1] Qing-zhi Yan[1] Xiao-dong Mao[1] Qiao Feng[1] Chang-chun Ge[1][1]Laboratory of Special Ceramics and Powder Metallurgy, University of Science and Technology Beijing, Beijing 100083, China [2]Beijing Chunshu Rectifier Co. Ltd., Beijing 100040, China

摘　要:
关键词:燃烧合成 反应堆 原材料 SiC 碳化硅合成 聚四氟乙烯 碳化硅粉末 制备
分类号:　TQ174.758 TL351.6[机标]文献标识码：文章编号：栏目信息：Materials
相关文献:主题相关 全文快照　　　

Preparation of β-SiC by combustion synthesis in a large-scale reactorAbstract:The feasibility of 5 kg β-SiC synthesized in one batch was demonstrated through igniting the mixture of Si, C-black and polytetrafluoroethylene （PTFE） under different nitrogen pressures. The effect of experimental parameters, including the contents of PTFE, nitrogen pressure, preheating, and raw materials distribution forms were investigated. The results show that the products are β-SiC with equiaxed grains. The average grain size is less than 200 nm. The powders loaded loosely promote reaction heat dispersing, resulting in small grains. High purity β-SiC powders are obtained when the PTFE content is as low as 5wt%, which simplifies the process and decreases the cost effectively. The ceramic sintered from the obtained β-SiC powders presents the hardness of 22.20 GPa, the bending strength as high as 715.15 MPa and the fracture toughness of 8.179 MPa·m^1/2, which are higher than those of ceramics fabricated with α-SiC produced by combustion synthesis.[著者文摘]

Key words:silicon carbide; combustion synthesis; β-SiC; reaction parameter; large-scale reactor; self-propagating high-temperature synthesis