PREPARATION OF ALPHA-ALUMINA CERAMICS - THE USE OF BOEHMITE SOLS AS DISPERSING AGENTS

被引:21
作者
KINDL, B
CARLSSON, DJ
DESLANDES, Y
HODDENBAGH, JMA
机构
[1] Division of Chemistry, National Research Council of Canada, Ottawa
关键词
D O I
10.1016/0272-8842(91)90032-U
中图分类号
TQ174 [陶瓷工业]; TB3 [工程材料学];
学科分类号
0805 ; 080502 ;
摘要
A method is reported tor the production of monolithic (400-500 g) alumina ceramics from slips of submicron alpha-alumina (Al2O3) powder using boehmite (AlOOH) sols as dispersion and sintering aids. Some commercial boehmite sols can be modified by acid and heat treatment so as to significantly improve the dispersing ability of the sols toward alpha-alumina compared to an acid-only treated sol. In addition, shrinkages of less than 15% occurred on drying these slips. The ceramics obtained on sintering the dried slips have microhardness and toughness properties comparable to those previously reported for fully densified alpha-alumina samples. The densities of the ceramics were all within 97% of the theoretical maximum. Differences between the heat-treated and untreated sols are proposed.
引用
收藏
页码:347 / 350
页数:4
相关论文
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