Method for preparing configured silicon carbide whisker-reinforced alumina ceramic articles

Patent · Wed Dec 31 23:00:00 EST 1986

OSTI ID:866191

Tiegs, Terry N ^[1]

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1. Lenoir City, TN

A ceramic article of alumina reinforced with silicon carbide whiskers suitable for the fabrication into articles of complex geometry are provided by pressureless sintering and hot isostatic pressing steps. In accordance with the method of the invention a mixture of 5 to 10 vol. % silicon carbide whiskers 0.5 to 5 wt. % of a sintering aid such as yttria and the balance alumina powders is ball-milled and pressureless sintered in the desired configuration in the desired configuration an inert atmosphere at a temperature of about 1800.degree. C. to provide a self-supporting configured composite of a density of at least about 94% theoretical density. The composite is then hot isostatically pressed at a temperature and pressure adequate to provide configured articles of at least about 98% of theoretical density which is sufficient to provide the article with sufficient strength and fracture toughness for use in most structural applications such as gas turbine blades, cylinders, and other components of advanced heat engines.

• Research Organization: LOCKHEED MARTIN ENRGY SYST INC
• DOE Contract Number: AC05-84OR21400
• Assignee: United States of America as represented by United States (Washington, DC)
• Patent Number(s): US 4652413
• OSTI ID: 866191
• Country of Publication: United States
• Language: English

Related Subjects

/264/501/
10
1800
94
98
accordance
adequate
advanced
alumina
alumina ceramic
alumina powder
applications
article
articles
atmosphere
balance
ball-milled
blades
carbide
carbide whisker
carbide whisker-reinforced
carbide whiskers
ceramic
ceramic article
ceramic articles
complex
complex geometry
components
composite
configuration
configured
cylinders
degree
density
desired
desired configuration
engines
fabrication
fracture
fracture toughness
gas
gas turbine
geometry
heat
heat engine
heat engines
hot
hot isostatic
hot isostatically
inert
inert atmosphere
isostatic
isostatic pressing
isostatically
isostatically pressed
method
mixture
powders
preparing
pressed
pressing
pressure
pressureless
pressureless sintering
provide
provided
reinforced
self-supporting
silicon
silicon carbide
sintered
sintering
steps
strength
structural
structural applications
sufficient
sufficient strength
suitable
temperature
theoretical
theoretical density
toughness
turbine
turbine blade
turbine blades
vol
whisker-reinforced
whiskers
wt
yttria