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

Patent · Thu Jan 01 00:00:00 EST 1987

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: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
• 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

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