Mo-La_2O_3阴极碳化层组织结构研究  

Microstructures of Mo-La_2O_3 Cathode Carbonized Layer

作　　者：周文元[1] 张久兴[1] 周美玲[1] 相志磊[1] 

机构地区：[1]北京工业大学材料科学与工程学院,北京100022

出　　处：《中国稀土学报》2010年第5期586-590,共5页Journal of the Chinese Society of Rare Earths

基　　金：国家重点基础研究发展规划资助项目(G1998061316)

摘　　要：采用高分辨透射/扫描电镜,X射线衍射和俄歇探针等分析手段对实用型的FU-6051电子管的碳化Mo-La2O3阴极显微组织结构进行了观察分析。碳化Mo-La2O3阴极碳化层为疏松多孔的Mo2C块状组织,其中有许多垂直于丝轴方向的晶界与孔洞串,相互贯通直至阴极表面。碳化层与芯部基体钼结合良好,两者间无明显的过渡层。活性物质La2O3在阴极的碳化层和基体中分布均匀,但在阴极表面有相当程度的富集。La2O3在碳化层中以两种方式存在:在晶界、孔洞中以微米级的颗粒富集,在Mo2C晶体内部弥散分布纳米级La2O3粒子。The microstructures,the sub-structure of the carbonized layer and the interface structure between carbonized layer and core molybdenum of practical Mo-La2O3 cathodes were studied with high distinguish scanning/transmission electron microscopes.The carbonized layer was composed of coarse Mo2C particles with lots of grain boundary crevices and mini-holes arranging perpendicular to the wire axle and up to surface.It was shown that the sub-structure of carbonized layer was loose and lots of nanometer La2O3 particles dispersed equably in the Mo2C crystals.The carbonized layer and core molybdenum were combined firmly,and there were no transition tissue between them.The micrometer La2O3 particles existed at the grain boundary crevices and mini-holes both in the carbonized layer and core molybdenum,but the nanometer La2O3 particles dispersed only in the carbonized layer.

关 键 词：镧钼阴极 碳化层 镧 微观组织与结构 

分 类 号：TG146[一般工业技术—材料科学与工程]