(1. 贛州有色冶金研究所 材料研究室，贛州 341000； 2. 中南大學(xué) 粉末冶金研究院, 長(zhǎng)沙 410083； 3. 南昌大學(xué) 材料科學(xué)與工程學(xué)院, 南昌 330031)
摘 要: 在相同的還原工藝參數(shù)下，以碳輔助氫還原法和普通氫還原法分別制備W粉，采用XRD、SEM、TEM和HRTEM對(duì)不同還原方法制得W粉的物相、形貌和粒度分布進(jìn)行對(duì)比研究，并討論還原方式對(duì)W粉粒徑和形貌的影響機(jī)理。結(jié)果表明：碳輔助氫還原W粉的還原長(zhǎng)大機(jī)制以固相局部化學(xué)反應(yīng)為主，平均粒徑均不超過(guò)60 nm，W粉一次顆粒呈均勻細(xì)小的球狀或橢球狀形貌，顆粒間沒(méi)有明顯的團(tuán)聚或粗化現(xiàn)象；普通氫還原以“揮發(fā)-沉積”長(zhǎng)大機(jī)制為主，所得W粉顆粒粗大，粒徑為微米級(jí)，發(fā)育完全，顆粒呈類球形多面體結(jié)構(gòu)，部分晶粒之間相互交聯(lián)。
關(guān)鍵字: W粉；碳輔助氫還原；長(zhǎng)大機(jī)制；粒度；形貌
（1. Department of Material Research, Ganzhou Nonferrous Metallurgy Research Institute, Ganzhou 341000, China; 2. Research Institute of Powder Metallurgy, Central South University, Changsha 410083, China; 3. School of Materials Science and Engineering, Nanchang University, Nanchang 330031, China）
Abstract:Tungsten powders were prepared by two different methods, respectively, carbon-hydrogen co-reduction method and common hydrogen reduction method, under same reduction process parameter. The phase, morphology and grain size of W powder samples were comparative studied by XRD, SEM, TEM and HRTEM. The effect mechanism of reduction method on the grain size and morphology of tungsten powders was investigated. The results show that the dominant growth mechanism of the carbon-hydrogen co-reduction method is solid phase topochemical reaction. The tungsten grains obtained by the co-reduction method are sphericity or spheroidicity with fine mean size of 60 nm. The agglomeration or coarsening phenomenon between tungsten particles is inconspicuous. The main growth mechanism of the common hydrogen reduction method is volatilization-sedimentation mechanism. The tungsten powders prepared by common hydrogen reduction are full-grown, and the grain morphology is roundish polyhedral. The grain size is micron order, and parts of the grains are bonded mutually.
Key words: tungsten powder; carbon-hydrogen co-reduction; growth mechanism; grain size; morphology
