CVD-produced boron filaments

Journal Article · Tue Jul 01 04:00:00 EDT 1980 · Ceram. Eng. Sci. Proc.; (United States)

DOI:https://doi.org/10.1002/9780470291030.ch5· OSTI ID:5591376

Wawner, F E ^[1]; Debolt, H E ^[2]

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1. Virginia, University, Charlottesville, Va.
2. Avco Corp., Avco Specialty Materials Div., Lowell, Mass.

A technique for producing boron filaments with an average tensile strength of 6.89 GPa has been developed which involves longitudinal splitting of the filament and core (substrate) removal by etching. Splitting is accomplished by a pinch wheel device which continuously splits filaments in lengths of 3.0 m by applying a force to the side of the filament to create a crack which is then propagated along the axis by a gentle sliding action. To facilitate the splitting, a single 10 mil tungsten substrate is used instead of the usual 0.5 mil substrate. A solution of hot 30% hydrogen peroxide is used to remove the core without attacking the boron. An alternative technique is to alter the residual stress by heavily etching the filament. Average strengths in the 4.83-5.52 GPa range have been obtained by etching an 8 mil filament to 4 mil.

• OSTI ID: 5591376
• Report Number(s): CONF-780181-; CONF-790194-
• Journal Information: Ceram. Eng. Sci. Proc.; (United States), Journal Name: Ceram. Eng. Sci. Proc.; (United States) Vol. 1; ISSN CESPD
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360301* -- Composite Materials-- Preparation & Fabrication-- (-1987)
BORON
CHEMICAL COATING
CHEMICAL VAPOR DEPOSITION
DEPOSITION
ELEMENTS
ETCHING
FABRICATION
FILAMENTS
MATERIALS
MECHANICAL PROPERTIES
METALS
REFRACTORY METALS
REINFORCED MATERIALS
RESIDUAL STRESSES
SEMIMETALS
STRESSES
SUBSTRATES
SURFACE COATING
SURFACE FINISHING
TRANSITION ELEMENTS
TUNGSTEN