Oxidation kinetics and high temperature in-situ observation of the oxidation behaviour of NbSi2 at 1023 K

被引：4

作者：

Zhang Fang ^{[1
]}

Zhang Lanting ^{[1
]}

Shan Aidang ^{[1
]}

Wu Jiansheng ^{[1
]}

机构：

[1] Shanghai Jiao Tong Univ, Sch Mat Sci & Engn, Key Lab Minist Educ High Temp Mat & Testing, Shanghai 200030, Peoples R China

来源：

SCIENCE IN CHINA SERIES E-TECHNOLOGICAL SCIENCES | 2006年 / 49卷 / 02期

基金：

中国国家自然科学基金;

关键词：

in-situ observation; high temperature optical microscopy; pesting phenomenon; silicides; oxidation; single crystal;

D O I：

10.1007/s11431-006-0147-x

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

By using high temperature optical microscopy, oxidation behaviors of poly- and single crystalline NbSi2 were observed in-situ at 1023 K. The effects of micro-cracks, porosity and grain boundary on the oxidation behavior of NbSi2 have been studied. The results indicate that new cracks initiate and extend from the pre-existing cracking areas in the arc-melted poly-crystalline specimen, leading to fragmentation after 220 min at 1023 K However, although pores and grain boundary are the preferential oxidation site, they do not directly lead to fragmentation during oxidation, indicating that the pre-existing cracks in specimen are the key reason to pesting. The oxidation kinetics of the studied NbSi2 specimens corresponds well with the in-situ observation.

引用

页码：147 / 155

页数：9

共 19 条

[11] High temperature oxidation and pesting of Mo(Si,Al)2 [J].