莫来石晶须制备新工艺与生长机理

New Growth Technology and Mechanism of Mullite Whiskers

本文首次提出了用Ａｌ２Ｏ３－ＳｉＯ２玻璃粉高温热处理制取莫来石晶须的新工艺．采用ＸＲＤ、ＳＥＭ和ＴＥＭ等手段研究了热处理温度制度及气氛对莫来石晶须生长的影响，确定了制备莫来石晶须的最佳工艺参数，所得莫来石晶须的直径为０．４～１．２Ｐｍ、长径比为１０～４０，其生长方向为ｃ轴方向，生成物中莫来石晶须的含量接近９８ｖｏｌ％．探讨了用Ａｌ２Ｏ３－ＳｉＯ２玻璃粉制取莫来石晶须的生长机理．

A new growth technology of mullite whiskers obtained by using A12O3-SiO2 glass powders was presented. The effect of heat-treatment temperature and reacting gas on the growth of mullite whiskers was studied by XRD, SEM and TEM. From the experimental results, a precipitation growth technology of mullite whiskers was obtained. Mullite whisker about 0.4￣l.2 pm in diameter and in 10￣40 aspact ratio was prepared, the whisker grew along the c-axis direction, and its content in products was about 98 vol%. Besides, growth mechanism of mullite whisker obtained by using A12O3-SiO2 glass powders was discussed.