高频热等离子体制备特种粉体研究进展  

Progress on preparation of special powders using HF thermal plasma

作　　者：袁方利[1] 金化成 侯果林 白柳杨[1] 丁飞[1] 李保强 陈运法[1] Fangli YUAN;Huacheng JIN;Guolin HOU;Liuyang BAI;Fei DING;Baoqiang LI;Yunfa(CHEN State Key Laboratory of Multi-phase Complex Systems,Institute of Process Engineering,Chinese Academy of Sciences,Beijing 100190,China)

机构地区：[1]中国科学院过程工程研究所材料与环境工程研究部多相复杂系统国家重点实验室

出　　处：《过程工程学报》2018年第6期1139-1145,共7页The Chinese Journal of Process Engineering

基　　金：国家自然科学基金资助项目(编号:11535003);多相复杂系统国家重点实验室自主部署课题(编号:MPCS-2015-A-01)

摘　　要：高频感应热等离子体具有能量密度大、温度高和冷却速率快等特点,是制备特种粉体的重要手段之一.本工作介绍了过程所在高频热等离子体制备特种粉体方面的研究进展.利用热等离子体的高温和快速冷却过程,粗颗粒经等离子体弧高温气化,通过控制冷却速率能得到纳米粉体,利用该方法制备了纳米球形硅、铁、钴和镍等粉体,纳米硅粉可用于锂离子电池负极材料.具有固定熔点的不规则颗粒在等离子体弧中经熔融形成球形液滴,快速冷却能获得规则致密的球形颗粒,通过等离子体球化制备了高熔点的钨、钼、铌、铬等规则致密的球形粉体.利用活性氢的瞬时强化还原反应,采用化学气相沉积能制备超细钨、钼、镍和铜等球形金属超细粉体.活性氧有助于调控颗粒的氧化生长过程,采用金属等的氧化反应可获得多种特殊形貌的氧化物.High frequency (HF)thermal plasma with high processing temperature (up to 10000K)in the flame zone and fast quenching rate (105-106K/s)at the flame tail is one of the most important methods to prepare special powders.In addition,thermal plasma is a powerful tool for synthesizing well-dispersed powders in a continuous and scalable process.In this manuscript,progress on preparation of special powders using HF thermal plasma in our team was introduced.Powders with large size were fed into plasma flame and vaporized to make them vaporation,and ultrafine powders were produced after fast quenching by physical vapor deposition (PVD).Spherical nanopowders of Si,Fe,Co,Ni could be prepared by PVD.Synthesized Si nanopowders display perfect spherical shape with smooth surface and good dispersity,which exhibit super electrochemical performance as anode for Li-ion batteries.Powders with irregular shape fed into plasma flame were melted to form spherical liquid drops and fast quenched to form spherical powders.W,Mo,Nb,Cr,Ni,Ti,V spherical powders could be prepared using HF thermal plasma. Hydrogen plasma with reactive radicals could help to enhance the hydrogen reductive reaction,which could make precursors to be reduced transiently to get metal nanopowders by chemical vapor deposition (CVD).W,Ni and Cu spherical nanopowders could be prepared using CVD.Synthesized W nanopowders with well defined spherical particles exhibit high sintering activity and strengthen the mechanical properties of obtained compacts.Oxygen plasma with reactive radicals can help to tune the growth of oxides in the plasma,and oxides with various morphologies can be produced using oxygen plasma.Al2O3 spherical nanopowders can be prepared and their sintering behavior shows that the aggregates are avoided and the grains are always uniform during sintering,owing to the employment of well dispersed spheres. Key learning points: (1)Research progress on preparation special powders using HF thermal plasma in our team was reviewed. (2)Powders with irregular shape

关 键 词：高频热等离子体 纳米粉体 球形粉体 氢活性粒子 物理气相沉积 化学气相沉积 

分 类 号：TB34[一般工业技术—材料科学与工程]