(1. 上海大学 上海市现代冶金与材料制备重点实验室，上海 200072；
2. 贵州大学 材料科学与冶金工程学院，贵阳 550003)
摘 要: 利用固体透氧膜(SOM)法电解还原Ta2O5制备金属钽，通过三相界面反应机制讨论了阴极微结构对电解过程及产物形貌的影响。结果表明：阴极片的颗粒尺寸与孔隙率是影响有效三相界线的重要因素；孔隙率大和粒度小均有利于电解还原的进行，孔隙率小会导致阴极产物形成致密的金属钽外层，阻碍阴极进一步脱氧；成型压力4 MPa时1 150 ℃烧结2 h制备的阴极片具有合适的孔隙率和粒度，电化学活性良好，电解产物形貌均匀，氧含量低。
关键字: 金属钽；五氧化二钽；三相界线；熔盐电解；SOM法
（1. Shanghai Key Laboratory of Modern Metallurgy and Materials Processing,
Shanghai University, Shanghai 200072, China;
2. School of Materials Science and Metallurgical Engineering, Guizhou University, Guiyang 550003, China）
Abstract: Tantalum metal was prepared by solid oxygen-ion conducting membrane (SOM) technology from Ta2O5 directly in molten CaCl2. Through the reaction mechanism of metal-oxide-electrolyte three-phase interline, the influence of pellets microstructure on the electrolysis process and products morphology were discussed. The results show that the particle size and porosity of cathode pellets are significant factors for three-phase interline during electrolysis process. Big porosity and small particle size of cathode pellets can enhance the rate of deoxidization. Contrarily, small porosity results in the formation of compact out-layer of tantalum metal. While the Ta2O5 pellet pressed by 4 MPa and sintered at 1 150 ℃ for 2 h has appropriate porosity and particle size, which has better electrochemical activation, the morphology of the products is uniform, and the oxygen content of the products is low.
Key words: tantalum metal; Ta2O5; three-phase interline; molten electrolysis; SOM process
