Oxidation kinetics of CVD silicon carbide and silicon nitride

Conference · Thu Oct 01 00:00:00 EDT 1992 · Ceramic Engineering and Science Proceedings; (United States)

OSTI ID:7201548

Fox, D S

The long-term oxidation behavior of pure, monolithic CVD SiC and Si3N4 is studied, and the isothermal oxidation kinetics of these two materials are obtained for the case of 100 hrs at 1200-1500 C in flowing oxygen. Estimates are made of lifetimes at the various temperatures investigated. Parabolic rate constants for SiC are within an order of magnitude of shorter exposure time values reported in the literature. The resulting silica scales are in the form of cristobalite, with cracks visible after exposure. The oxidation protection afforded by silica for these materials is adequate for long service times under isothermal conditions in 1-atm dry oxygen. 10 refs.

• OSTI ID: 7201548
• Report Number(s): CONF-920144-; CODEN: CESPD
• Journal Information: Ceramic Engineering and Science Proceedings; (United States), Vol. 13:9-10; Conference: 16. annual conference on composites, materials, and structures, Cocoa Beach, FL (United States), 13-16 Jan 1992; ISSN 0196-6219
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
COMPOSITE MATERIALS
OXIDATION
SILICON CARBIDES
SILICON NITRIDES
CHEMICAL REACTION KINETICS
CHEMICAL VAPOR DEPOSITION
CRACKS
DEPOSITS
SERVICE LIFE
SILICON OXIDES
TEMPERATURE RANGE 1000-4000 K
CARBIDES
CARBON COMPOUNDS
CHALCOGENIDES
CHEMICAL COATING
CHEMICAL REACTIONS
DEPOSITION
KINETICS
LIFETIME
MATERIALS
NITRIDES
NITROGEN COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PNICTIDES
REACTION KINETICS
SILICON COMPOUNDS
SURFACE COATING
TEMPERATURE RANGE
360604* - Materials- Corrosion
Erosion
& Degradation