Microwave and millimeter wave processing of polymer-derived silicon nitride

Book · Tue Dec 31 04:00:00 EST 1996

OSTI ID:504902

Schwab, S T; Timmons, S F; Blanchard, C R; Grimes, M D; Graef, R C ^[1]; Katz, J D; Rees, D E; Hardek, T W ^[2]

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1. Southwest Research Inst., San Antonio, TX (United States). Materials and Structures Div.
2. Los Alamos National lab., NM (United States)

Chemical methods of processing ceramics have the potential to overcome many of the processing-related obstacles that have hindered widespread commercialization. The Southwest Research Institute (SwRI) has focused on the development of polymeric precursors to silicon nitride (Si{sub 3}N{sub 4}). One such precursor, perhydropolysilazane (or PHPS), has been shown to be a useful binder for Si{sub 3}N{sub 4} powder processing, a useful matrix precursor for the polymer infiltration/pyrolysis (PIP) processing of fiber-reinforced Si{sub 3}N{sub 4}, and a useful ceramic coating precursor for the repair of oxidation protection coatings on carbon-carbon composites. While conventional, thermal pyrolyses of these preceramics has been sufficient to demonstrate their potential, substantial cost savings could be realized if the polymer-to-ceramic conversion could be instigated with electromagnetic energy. The authors have investigated the use of millimeter wave heating as a means of converting PHPS into Si{sub 3}N{sub 4}, and report here the results of the efforts to produce bulk compacts, coatings, and fiber-reinforced ceramics.

• OSTI ID: 504902
• Report Number(s): CONF-960401--; ISBN 1-55899-333-9
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BINDERS
COATINGS
COMPOSITE MATERIALS
EXPERIMENTAL DATA
MICROWAVE HEATING
ORGANIC SILICON COMPOUNDS
PHASE STUDIES
PYROLYSIS
SILICON CARBIDES
SILICON NITRIDES
SYNTHESIS