High temperature corrosion of silicon based ceramics in environments containing halogens and alkali halides
Conference
·
OSTI ID:20002621
Silicon carbide and other silicon-based ceramics obtain their oxidation resistance by the formation of protective silica films in oxygen containing environments. In the presence of chlorine or alkali chlorides, this film may not form, or may be unprotective, so that accelerated oxidation occurs. Chlorine and alkali halides may contribute to accelerated oxidation via three possible mechanisms. Active oxidation occurs at relatively low temperatures and high ratios of chlorine to oxygen, and is characterized by simultaneous formation of silicon chlorides and non-protective oxides. Silica film disruption occurs at higher temperatures when volatile chlorides format the interface between SiC and the Si0{sub 2} scale, and cause bubbles to form in the film. Alkali fluxing occurs in the presence of alkali chloride vapors. In alkali fluxing, a low melting glass is formed by the reaction between the alkali vapor species and silica rather than by reactions with chlorine itself.
- Research Organization:
- Univ. of Illinois at Chicago, IL (US)
- OSTI ID:
- 20002621
- Report Number(s):
- CONF-990401--
- Country of Publication:
- United States
- Language:
- English
Similar Records
Effects of chlorine and alkali chlorides on corrosion of silicon carbide based ceramics in combustion environments. Topical report, June 1, 1987-May 31, 1992
Oxidation of silicon, silicon carbide, and silicon nitride in gases containing oxygen and chlorine
High temperature corrosion of alloys and ceramics by alkali chlorides
Technical Report
·
Mon Aug 01 00:00:00 EDT 1994
·
OSTI ID:147497
Oxidation of silicon, silicon carbide, and silicon nitride in gases containing oxygen and chlorine
Journal Article
·
Tue Jun 01 00:00:00 EDT 1993
· Journal of the American Ceramic Society; (United States)
·
OSTI ID:6401617
High temperature corrosion of alloys and ceramics by alkali chlorides
Book
·
Tue Oct 01 00:00:00 EDT 1996
·
OSTI ID:376069