Synthesis of substitutional hexaboride of lanthanum and cerium La_(1-x)Ce_(x)B_(6) via aluminothermic reduction  

作　　者：Yu Wang Xiao-Hui Yang Jian Cui Guo-Hua Zhang 

机构地区：[1]State Key Laboratory of Advanced Metallurgy,University of Science and Technology Beijing,Beijing,100083,China [2]Beijing Key Laboratory of Green Recovery and Extraction of Rare and Precious Metals,University of Science and Technology Beijing,Beijing 100083,China

出　　处：《Journal of Rare Earths》2023年第11期1780-1788,I0005,共10页稀土学报（英文版）

基　　金：financially supported by State Key Laboratory of Advanced Metallurgy,University of Science and Technology Beijing,China。

摘　　要：Rare-earth hexaborides(REB_(6))are vital raw materials for cathode materials and high temperature structural ceramics that are widely applied as high-frequency electron tubes and ceramics adaptive for extreme environment,respectively.In this work,single phase substitutional solid solution REB_(6)(LaB_(6),La_(0.75)Ce_(0.25)B_(6).La_(0.5)Ce_(0.5)B_(6),La_(0.25)Ce_(0.75)B_(6) and CeB_(6))powders were prepared with the raw materials of La_(2)O_(3),CeO_(2),B_(4)C and Al powders,after calcining at 1773 K for 4 h and the following alkaline leaching.All substitutional solid solution products have homogeneous distributions of La and Ce in particles.Through microscopic morphology analysis,it is discovered that the formation of solid solution is beneficial for reducing the particle size of product,relative to LaB_(6) and CeB_(6).Moreover,Al flux plays an important role in decarbonizing reaction,and C contents of all products are below 0.4 wt%.

关 键 词：HEXABORIDE Substitutional solid solution Aluminothermic reduction Rare earths 

分 类 号：TG1[金属学及工艺—金属学]