Preparation and use of a boron nitride precursor as binder for the densification of boron nitride

Journal Article · Thu Feb 01 00:00:00 EST 1990 · Journal of the American Ceramic Society; (USA)

DOI:https://doi.org/10.1111/j.1151-2916.1990.tb06509.x· OSTI ID:6820001

Maya, L; Angelini, P ^[1]

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1. Oak Ridge National Lab., TN (USA)

A precursor of boron nitride was prepared through the partial condensation of 2,4,6-trichloroborazine and bis-(trimethylsilyl)acetylene. This reaction was conducted at 100{degrees}C and is catalyzed by AlCl{sub 3}. The condensation product pyrolyzed at 800{degrees}C, producing trimethylsilyl chloride as a volatile product and a boron nitride rich residue containing 54 wt% of the initial weight. Mixtures of the precursor and commercial boron nitride were made and hot-pressed at 800{degrees}C and 27.6 MPa. A maximum density of 1.84 g/cm{sup 3} is reached at a loading corresponding to the deposition of 13 wt% residue derived from the precursor. Examination by analytical electron microscopy, including x-ray energy dispersive spectroscopy and electron energy loss spectroscopy analyses, revealed the location of material derived from the precursor in BN-binder composites through the presence of residual aluminum, silicon, and carbon. Crystallization of boron nitride from the precursor appears to have taken place, as deduced from the morphology of the phases observed and association with residual elements present in the binder.

• DOE Contract Number: AC05-84OR21400
• OSTI ID: 6820001
• Journal Information: Journal of the American Ceramic Society; (USA), Vol. 73:2; ISSN 0002-7820
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ALUMINIUM CHLORIDES
CATALYTIC EFFECTS
BORON NITRIDES
CHEMICAL PREPARATION
BINDERS
CHEMICAL REACTION KINETICS
ELECTRON MICROSCOPY
HOT PRESSING
PHASE STUDIES
PRECURSOR
X-RAY SPECTRA
ALUMINIUM COMPOUNDS
BORON COMPOUNDS
CHLORIDES
CHLORINE COMPOUNDS
FABRICATION
HALIDES
HALOGEN COMPOUNDS
KINETICS
MATERIALS WORKING
MICROSCOPY
NITRIDES
NITROGEN COMPOUNDS
PNICTIDES
PRESSING
REACTION KINETICS
SPECTRA
SYNTHESIS
360201* - Ceramics
Cermets
& Refractories- Preparation & Fabrication
360202 - Ceramics
Cermets
& Refractories- Structure & Phase Studies
400101 - Activation
Nuclear Reaction
Radiometric & Radiochemical Procedures