Oxidation kinetics of CVD silicon carbide and silicon nitride

Fox, D S

Title: Oxidation kinetics of CVD silicon carbide and silicon nitride

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Abstract

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.

Authors:: Fox, D S

Publication Date:: Thu Oct 01 00:00:00 EDT 1992

OSTI Identifier:: 7201548

Report Number(s):: CONF-920144-
Journal ID: ISSN 0196-6219; CODEN: CESPD

Resource Type:: Conference

Journal Name:: Ceramic Engineering and Science Proceedings; (United States)

Additional Journal Information:: Journal Volume: 13:9-10; Conference: 16. annual conference on composites, materials, and structures, Cocoa Beach, FL (United States), 13-16 Jan 1992; Journal ID: ISSN 0196-6219

Country of Publication:: United States

Language:: English

Subject:: 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

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                    Fox, D S. Oxidation kinetics of CVD silicon carbide and silicon nitride.  United States: N. p., 1992. 
        Web.

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                    Fox, D S. Oxidation kinetics of CVD silicon carbide and silicon nitride.  United States.

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                    Fox, D S. 1992.  
        "Oxidation kinetics of CVD silicon carbide and silicon nitride".  United States.

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@article{osti_7201548,

  title        = {Oxidation kinetics of CVD silicon carbide and silicon nitride},

  author       = {Fox, D S},

  abstractNote = {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.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/7201548},
  journal      = {Ceramic Engineering and Science Proceedings; (United States)},

  issn         = {0196-6219},

  number       = ,

  volume       = 13:9-10,

  place        = {United States},

  year         = {Thu Oct 01 00:00:00 EDT 1992},

  month        = {Thu Oct 01 00:00:00 EDT 1992}

}

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