等离子喷涂铝电解可湿润TiB_2阴极涂层研究进展  

Research Progress in Plasma Spraying TiB_2 Coating of Wettable Cathodes for Aluminum Electriclysis

作　　者：彭如振[1] 李荣兴[1] 俞小花[1] 侯彦青[1] 谢刚[2] 

机构地区：[1]昆明理工大学冶金与能源工程学院,昆明650093 [2]云南冶金集团昆明冶金研究院,昆明650031

出　　处：《表面技术》2016年第4期116-123,161,共9页Surface Technology

基　　金：横向科技开发(KKK0201352107)~~

摘　　要：铝电解工业越来越多的采用石墨阴极,石墨阴极具有良好的导电性能,但石墨不被铝液湿润且和铝液形成Al_4C_3,导致铝电解槽运行寿命短。可湿润TiB_2涂层阴极因节能和延长槽寿命能够给铝电解工业带来显著效益。等离子喷涂是一种高效、灵活的沉积涂层的方法,能够在形状复杂或大表面积的基体上沉积金属间化合物、陶瓷或复合材料,涂层厚度可从数微米到数毫米。等离子喷涂制备可湿润性TiB_2涂层阴极是可行有效的方法,本文评述了等离子喷涂制备可湿润TiB_2阴极涂层的研究进展,简述了等离子喷涂工艺受到的影响因素(包括粉末性质、基体表面形貌和焰流性质)和涂层与基体材料结合的机制(包括机械结合、冶金结合和物理结合),分析和讨论了TiB_2粉末制备、基体预处理、等离子喷涂工艺参数、涂层显微结构和性能等。最后,指出了等离子喷涂制备可湿润性TiB_2涂层阴极工艺将来研究需要解决的几个关键问题。Graphite is used increasingly as cathode for aluminium electrolysis cell,which shows a better electrical conductivity and less energy loss in the process. Liquid aluminum does not wet graphite,and react with graphite to form aluminium carbide（ Al4C3）,which is the cause that limits the lifespan of cathodes. The TiB2 coating of wettable cathodes has the potential to give enormous benefits to the aluminum electrolysis industry in terms of energy cost saving and prolonged cell life. Plasma spraying is a cost-effective and highly flexible method for depositing coatings including intermetallics,ceramics and composites with a thickness from several micrometers to millimeters on substrates of complicated shapes and with a large area. Plasma Sprayed TiB2 coating of wettable cathodes is a known technique. This review covers the development of plasma sprayed TiB2 coatings of wettable cathodes for aluminum electrolysis. This article outlined the influencing factors of plasma spraying（ including the powder properties,the surface morphology of substrate material and the flame flow properties）,and the binding mechanism between coatings materials and substrate materials（ including mechanical bonding,metallurgical bonding and physical bonding）. The TiB2 powder preparation,pretreatment of carbon blocks and plasma spraying process were reviewed,and then the microstructure and properties of plasma spraying TiB2 coatings were discussed. At the end,some key problems in the future researches of plasma spraying TiB2 coating of wettable cathodes were also outlined.

关 键 词：等离子喷涂 可湿润阴极 TIB2涂层 结合机制 氧化 导电性 

分 类 号：TG174.442[金属学及工艺—金属表面处理]