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采用重力分离ＳＨＳ技术结合旋转工艺制备了陶瓷内衬复合弯管，在添加ＳｉＯ２的基础上，重点研究了ＮａＦ添加剂对复合弯管合成过程及组织性能的影响。研究发现，ＮａＦ以Ｎａ３ＡｌＦ６冰晶石结构和Ｎａ２ＳｉＯ３单斜结构存在于陶瓷枝晶晶界上，并因“成分过冷”，使陶瓷枝晶细密；在铝热燃烧过程中ＮａＦ作为稀释剂存在，降低燃烧温度和蔓延速率；在陶瓷凝固过程中，ＮａＦ通过降低熔体结晶温度和熔体动力粘度而促使陶瓷致密。
Based on the addition of SiO2, the effects of NaF additive on the synthesis process and the microstructure of the composite elbow were studied emphatically by using the gravity separation SHS technology combined with the rotary process. The results show that NaF exists in the grain boundary of ceramic dendrites with Na3AlF6 cryolite and Na2SiO3 monoclinic structure, and the dendrite is fine due to “cold” composition. NaF exists as a diluent during hot aluminization and decreases Burning temperature and spreading rate; during the solidification of ceramics, NaF promotes the densification of ceramics by lowering the melt crystallization temperature and the melt kinetic viscosity.