高等学校化学学报

高等学校化学学报 ›› 1995, Vol. 16 ›› Issue (3): 440.

• 论文 • 上一篇    下一篇

超细海棉镍的烧结行为考察

范崇正, 吴佑实, 李剑敏   

  1. 中国科学技术大学化学物理系, 合肥 230026
  • 收稿日期:1994-04-30 修回日期:1994-09-07 出版日期:1995-03-24 发布日期:1995-03-24
  • 通讯作者: 范崇正,男,49岁,副教授.
  • 作者简介:范崇正,男,49岁,副教授.
  • 基金资助:

    国家科学技术委员会资助

An Investigation in the Sintering Behaviour of Super Fine Sponge-Nickel

FAN Chong-Zheng, WU You-Shi, LI Jian-Min   

  1. Department of Chemical Physics, University of Science and Technology, of China, Hefei 230026
  • Received:1994-04-30 Revised:1994-09-07 Online:1995-03-24 Published:1995-03-24

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被引次数

1

摘要： 用化学法制得比表面积为74.7m2/g的超细海棉镍,其平均粒度为2～5nm.在375～600℃范围内的不同气氛中进行烧结,并在一定时间间隔内对样品进行表面积测定,且采用扫描电镜、透射电镜、X射线衍射等手段对烧结前后的样品进行对比。结果表明,微细镍颗粒在400℃即已有明显烧结;烧结使表面积减小,颗粒度增大,结晶度提高;在不同气氛中烧结程度不同,在He、N2、H2中烧结程度依次减轻;开始烧结阶段,表面积下降迅速,其后变化明显减缓。

关键词: 超细海棉镍, 烧结程度, 速率方程, 颗粒迁移与原子迁移机理

Abstract: Super fine sponge-Ni material was obtained by the method of chemistry, which has the surface area of 74. 7m2/g and average of particle size of 2-5nm. After sintering in the range of 375～600℃ and in different gases at each time interval, the samples were taken out and instrumental methods of SSA, SEM, TEM, XRD were used to detect their sintering extents respectively. It is found that the sintering takes place at 400℃ evidently; sintering reduces the surface area, increases the particle size, and develops crystallization: and that in different gases the SSA follows the order: He<N2<H2In the present work the sintering rate equationis established. it is advanced that during the initial fast sintering stage,the main mechanism is particle migrationi while at the following slow sintering stage,the main mechanism is atom migration. The accompanying phenomena in sintering process are discussed also.

Key words: Super fine sponge-Ni, Sintering extent, Rate equation, Mechanism of particlemigration and of atom migration

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