碳热还原法制备V_8C_7粉体  

Preparation of V_8C_7 powders by carbothermal reduction method

作　　者：任杰[1,2] 方民宪[2] 陈敏[2] 

机构地区：[1]西华大学材料科学与工程学院,四川成都610039 [2]攀枝花学院材料工程学院,四川攀枝花617000

出　　处：《中国粉体技术》2016年第4期47-49,共3页China Powder Science and Technology

基　　金：四川省应用基础研究项目;编号:2014JY0132;攀枝花市创新人才培养项目;编号:2015TX-11

摘　　要：以偏钒酸铵、二氧化钛及石墨为原料,采用碳热还原法,成功制备V_8C_7粉体;采用X射线衍射物相分析、热重-差热分析、扫描电镜形貌观察以及粒度分析等方法研究偏钒酸铵碳热还原制备V_8C_7的还原过程,优化了配碳系数。结果表明:低温一次还原以偏钒酸铵脱氨脱水分解反应以及低价钒氧化物的形成为主;高温二次还原以钒氧化物向非化学计量VC_x的转化为主;随着配碳系数的增加,反应产物VC_x的晶格常数不断增大;当反应温度为1 500℃、配碳系数为0.9时可获得钒原子和碳原子有序排列的单相V_8C_7,粒径约为2.7μm。V8C7 powders were prepared by the carbothermal reduction method taking ammonium metavanadate, titanium dioxide and graphite as raw materials. The reduction process of ammonium metavanadate was investigated with combination of XRD, TG-DSC, SEM and particle analysis methods and the carbon coefficient was optimized. Results show that in the period of once low-temperature reduction, major reactions are decomposition of ammonium and formation of vanadium sub-oxides. During the second high-temperature vacuum reduction, the vanadium oxides convert to the reduction products of non-stoichiometry VCx. The lattice constants of VCx increase with carbon coefficient increasing. When the reaction temperature is 1 500 ℃ and the carbon coefficient is 0.9, single phase V8C7 is obtained with orderly arrangement of vanadium atoms and carbon atoms. The grain size is about 2.7 μm.

关 键 词：偏钒酸铵 碳热还原 配碳系数 

分 类 号：TF123[冶金工程—粉末冶金]