High density hexagonal boron nitride prepared by hot isostatic pressing in refractory metal containers

Patent · Wed Jan 01 00:00:00 EST 1992

OSTI ID:868307

Hoenig, Clarence L ^[1]

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1. Livermore, CA

Boron nitride powder with less than or equal to the oxygen content of starting powder (down to 0.5% or less) is hot isostatically pressed in a refractory metal container to produce hexagonal boron nitride with a bulk density greater than 2.0 g/cc. The refractory metal container is formed of tantalum, niobium, tungsten, molybdenum or alloys thereof in the form of a canister or alternatively plasma sprayed or chemical vapor deposited onto a powder compact. Hot isostatic pressing at 1800.degree. C. and 30 KSI (206.8 MPa) argon pressure for four hours produces a bulk density of 2.21 g/cc. Complex shapes can be made.

• Research Organization: Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
• DOE Contract Number: W-7405-ENG-48
• Assignee: United States of America as represented by United States (Washington, DC)
• Patent Number(s): US 5116589
• OSTI ID: 868307
• Country of Publication: United States
• Language: English

Related Subjects

density
hexagonal
boron
nitride
prepared
hot
isostatic
pressing
refractory
metal
containers
powder
equal
oxygen
content
starting
isostatically
pressed
container
produce
bulk
cc
formed
tantalum
niobium
tungsten
molybdenum
alloys
form
canister
alternatively
plasma
sprayed
chemical
vapor
deposited
compact
1800
degree
30
ksi
206
mpa
argon
pressure
hours
produces
21
complex
shapes
powder compact
hot isostatically
nitride powder
bulk density
plasma spray
oxygen content
vapor deposited
refractory metal
chemical vapor
boron nitride
hot isostatic
isostatic pressing
isostatically pressed
plasma sprayed
metal container
argon pressure
metal containers
alternatively plasma
complex shapes
hours produces
complex shape
/264/423/501/