摘要
以Nb205和NaAl02的混合粉末为原料，NaCl和CaCl2为稀释剂，金属钠为还原剂，采用熔盐中金属钠热还原法制各铌铝金属间化合物粉末。研究原料中氧与熔盐中CaCl2的物质的量比、原料粉末中铌与铝的物质的量以及预熔时间对铌铝金属间化合物粉末物相结构、形貌及粒度的影响。结果发现，在NaCl．52％CACl2体系（摩尔分数，下同）中，预熔时间约为6．0h，在680℃条件下还原Nb205．85．7％NaAl02（摩尔分数，下同）混合粉末的产物为NbAl3纳米粉末；在750℃条件下还原Nab205．40．0％NaAl02混合粉末获得Nb3A1纳米粉末。NbAl3粉末和Nb，A1粉末的粒径分别在50～260nm和30～180nm范围内。随着原料在熔盐体系中预熔时间延长，铌铝金属间化合物粉末的纯度提高。
The niobium aluminides intermetallic particles were prepared by a sodiothermic reduction process using Nb2O5 and NaAlO2 as raw materials, NaCl and CaCl2 as the diluents and sodium as a reducing agent. The phases, morphology and particle size of niobium aluminides intermetallic powders depending on the molar ratio of oxygen in raw materials and CaCl2 in the molten salt, the atomic ratio of niobium and aluminum in raw materials and premelting time in molten salts were analyzed. The Nbl3 and Nb3Al particles are obtained at 680℃ and 750 ℃ for the 6.0 h premelting time, respectively, and the particle size of NbAl3 and Nb3Al powders is about 50-260 nm and 30-180 nm. Besides, the purity of the niobium aluminides intermetallics powders was increased along with the increasing of the premelting time.
出处
《粉末冶金材料科学与工程》
EI
北大核心
2013年第2期281-289,共9页
Materials Science and Engineering of Powder Metallurgy
基金
国家科学自然基金资助项目(51004008
21071014)
关键词
铌铝金属间化合物
NB2O5
钠热还原法
熔盐介质
niobium aluminides intermetallics
Nb2O5
sodiothermic reduction process
molten salts
