(1. 上海大學(xué) 上海市現(xiàn)代冶金與材料制備重點(diǎn)實(shí)驗(yàn)室,上海 200072;
2. 貴州大學(xué) 材料科學(xué)與冶金工程學(xué)院,貴陽(yáng) 550003)
摘 要: 利用固體透氧膜(SOM)法電解還原Ta2O5制備金屬鉭,通過(guò)三相界面反應(yīng)機(jī)制討論了陰極微結(jié)構(gòu)對(duì)電解過(guò)程及產(chǎn)物形貌的影響。結(jié)果表明:陰極片的顆粒尺寸與孔隙率是影響有效三相界線的重要因素;孔隙率大和粒度小均有利于電解還原的進(jìn)行,孔隙率小會(huì)導(dǎo)致陰極產(chǎn)物形成致密的金屬鉭外層,阻礙陰極進(jìn)一步脫氧;成型壓力4 MPa時(shí)1 150 ℃燒結(jié)2 h制備的陰極片具有合適的孔隙率和粒度,電化學(xué)活性良好,電解產(chǎn)物形貌均勻,氧含量低。
關(guān)鍵字: 金屬鉭;五氧化二鉭;三相界線;熔鹽電解;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


