Development of silicon nitride composites with continuous fiber reinforcement

Technical Report · Fri Oct 01 04:00:00 EDT 1993

DOI:https://doi.org/10.2172/10192173· OSTI ID:10192173

Starr, T L; Mohr, D L; Lackey, W J; Hanigofsky, J A ^[1]

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1. Georgia Inst. of Tech., Atlanta, GA (United States). Georgia Technology Research Inst.

The composites were fabricated using ultrafine Si powders prepared by attritor milling; the powders exhibits full conversion to Si nitride in < 3 h at {le} 1200 C (these conditions reduce degradation of the fibers compared to conventional). Effects of processing conditions on fiber properties and the use of fiber coatings to improve stability during processing as well as change the fiber-matrix interfacial properties were investigated. A duplex carbon-silicon carbide coating, deposited by CVD, reduced fiber degradation in processing, and it modified the fiber-matrix adhesion. Si nitride matrix composites were fabricated using reaction sintering, forming laminates, filament-wound plates, and tubes. In each case, an attritor milled Si powder slurry is infiltrated into ceramic fiber preforms or tows, which are then assembled to form a 3-D structure for reaction sintering. The resulting composites have properties comparable to chemical vapor infiltration densified composites, with reasonable strengths and graceful composite fracture behavior.

• Research Organization: Oak Ridge National Lab., TN (United States); Georgia Inst. of Tech., Atlanta, GA (United States). Georgia Technology Research Inst.
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC05-84OR21400
• OSTI ID: 10192173
• Report Number(s): ORNL/Sub--87-00184/04; ON: DE94001996
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360601
CARBON
CHEMICAL VAPOR DEPOSITION
COATINGS
COMPOSITE MATERIALS
FABRICATION
FIBERS
NITRIDATION
PREPARATION AND MANUFACTURE
REINFORCED MATERIALS
SILICON
SILICON CARBIDES
SILICON NITRIDES
TEXTILES