Fabrication and properties of ceramic composites with a boron nitride matrix

Journal Article · Thu Jun 01 04:00:00 EDT 1995 · Journal of the American Ceramic Society

DOI:https://doi.org/10.1111/j.1151-2916.1995.tb08850.x· OSTI ID:82623

Kim, D P; Cofer, C G; Economy, J ^[1]

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1. Univ. of Illinois, Urbana, IL (United States). Dept. of Materials Science and Engineering

Boron nitride (BN) matrix composites reinforced by a number of different ceramic fibers have been prepared using a low-viscosity, borazine oligomer which converts in very high yield to a stable BN matrix when heated to 1,200 C. Fibers including Nicalon (SiC), FP (Al{sub 2}O{sub 3}), Sumica and Nextel 440 (Al{sub 2}O{sub 3}-SiO{sub 2}) were evaluated. The Nicalon/BN and Sumica/BN composites displayed good flexural strengths of 380 and 420 MPa, respectively, and modulus values in both cases of 80 GPa. On the other hand, FP/BN and Nextel/BN composites exhibited very brittle behavior. Nicalon fiber with a carbon coating as a buffer barrier improved the strength by 30%, with a large amount of fiber pullout from the BN matrix. In all cases except for Nicalon, the composites showed low dielectric constant and loss.

• Sponsoring Organization: USDOE
• OSTI ID: 82623
• Journal Information: Journal of the American Ceramic Society, Journal Name: Journal of the American Ceramic Society Journal Issue: 6 Vol. 78; ISSN 0002-7820; ISSN JACTAW
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM OXIDES
ALUMINIUM SILICATES
BORON NITRIDES
CARBON
COATINGS
COMPOSITE MATERIALS
DIELECTRIC PROPERTIES
FABRICATION
FLEXURAL STRENGTH
FRACTURE PROPERTIES
INFRARED SPECTRA
ORGANIC BORON COMPOUNDS
PYROLYSIS
SCANNING ELECTRON MICROSCOPY
SILICON CARBIDES
X-RAY DIFFRACTION