稀土Y对超细W-Ni-Fe复合粉末制备效果的影响  

Influence of Y contents on preparative effect of ultra-fine W-Ni-Fe composite powders

作　　者：彭石高[1] 范景莲[1] 刘涛[1] 祁美贵[1] 丁飞[1] 田家敏[1] 

机构地区：[1]中南大学粉末冶金国家重点实验室,长沙410083

出　　处：《粉末冶金材料科学与工程》2008年第2期106-110,共5页Materials Science and Engineering of Powder Metallurgy

基　　金：国家自然科学基金资助项目(50674106);国家高技术研究发展计划(863计划)资助项目(2006AA03A213)

摘　　要：采用溶胶-喷雾干燥-氢还原法制备含稀土Y的超细90W-7Ni-3Fe复合粉末,通过X射线衍射仪分析其还原过程中的粉末物相变化,并用扫描电子显微镜观察所制粉末的大小和形貌,研究稀土Y对超细复合粉末制备效果的影响。结果表明:经600℃煅烧2 h的前驱体粉末中稀土Y以复合氧化物Y2W3O12的形式存在,Y含量对稀土复合氧化物的组成有很大影响,采用450℃/30 min+750℃/90 min的两步法进行还原,稀土Y的含量为5%时,稀土Y最终以Y2WO6的形式存在;稀土Y的含量为10%及20%时,稀土Y均以Y2WO6和Y6W2O15两种低价复合氧化物的形式存在。Y含量越大,粉末粒度越细。Ultra-fine W-Ni-Fe composite powders with the addition of rare earth Y were prepared by sol-spray drying calcination and subsequent hydrogen reduction process, X-ray diffraction（XRD） and scanning electron microscopy（SEM） were used to analyse the influence of rare earth Y contents during preparing the composite powders. The results show that the amorphous spray-dried precursors transform into composite-oxide powders, a composite oxide phase of Y and W forms as Y2W3O12 and increases with adding more Y. With hydrogen reduction by two-stage process of 450℃/30 min＋750 ℃/90 min, a new phase Y2WO6 forms with the addition of 5% Y, while the new phases, Y2WO6 and Y6W2O15, form with the addition of 10%Y and 20%Y.

关 键 词：W-Ni-Fe复合粉末 纳米级粉末 氢还原 稀土Y 

分 类 号：TF125.2[冶金工程—粉末冶金] TG146.4[冶金工程—冶金物理化学]