Oxidation of SIC powders in SiC/alumina/zirconia compacts

被引：35

作者：

Lin, YJ ^{[1
]}

Chen, LJ ^{[1
]}

机构：

[1] Tatung Univ, Dept Mat Engn, Taipei, Taiwan

来源：

CERAMICS INTERNATIONAL | 2000年 / 26卷 / 06期

关键词：

activation energy; powders; SiC;

D O I：

10.1016/S0272-8842(99)00102-9

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：

Oxidation of SiC powder in compacts of SiC/alumina/zirconia was studied between 1000 and 1200 degrees C in air for up to 10 h. The thermogravimetric analysis showed that the weight gain due to passive SiC powder oxidation became significant at temperatures greater than or equal to 937 degrees C. After oxidation, the particle usually consisted of a SiC core surrounded by a layer of amorphous silica. However, the amorphous layer would crystallize into cristobalite if the powders were oxidized at 1200 degrees C for a longer time (greater than or equal to 8 h). The oxidation rate decreased if cristobalite formed: The square of weight gain fraction after oxidation was linearly proportional to the oxidation time when the weight gain fraction was less than 0.34. The activation energy of the oxidation of SIC powders was estimated to be 213.1 kJ/mol. (C) 2000 Elsevier Science Ltd and Techna S.r.l. All rights reserved.

引用

页码：593 / 598

页数：6

共 23 条

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