High-temperature zirconia insulation and method for making same

Patent · Fri Jan 01 00:00:00 EST 1988

OSTI ID:866581

Wrenn, Jr., George E. ^[1]; Holcombe, Jr., Cressie E. ^[2]; Lewis, Jr., John ^[3]

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1. (Clinton, TN)
2. (Knoxville, TN)
3. (Oak Ridge, TN)

The present invention is directed to a highly pure, partially stabilized, fibrous zirconia composite for use as thermal insulation in environments where temperatures up to about 2000.degree. C. are utilized. The composite of the present invention is fabricated into any suitable configuration such as a cone, cylinder, dome or the like by vacuum molding an aqueous slurry of partially stabilized zirconia fibers into a desired configuration on a suitably shaped mandrel. The molded fibers are infiltrated with zirconyl nitrate and the resulting structure is then dried to form a rigid structure which may be removed and placed in a furnace. The structure is then heated in air to a temperature of about 600.degree. C. for driving off the nitrate from the structure and for oxidizing the zirconyl ion to zirconia. Thereafter, the structure is heated to about 950.degree. to 1,250.degree. C. to fuse the zirconia fibers at their nexi in a matrix of zirconia. The composite produced by the present invention is self-supporting and can be readily machined to desired final dimensions. Additional heating to about 1800.degree. to 2000.degree. C. further improves structural rigidity.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
• DOE Contract Number: W-7405-ENG-26
• Assignee: Martin Marietta Energy Systems Inc. (Oak Ridge, TN)
• Patent Number(s): US 4743340
• OSTI ID: 866581
• Country of Publication: United States
• Language: English

Related Subjects

high-temperature
zirconia
insulation
method
directed
highly
pure
partially
stabilized
fibrous
composite
thermal
environments
temperatures
2000
degree
utilized
fabricated
suitable
configuration
cone
cylinder
dome
vacuum
molding
aqueous
slurry
fibers
desired
suitably
shaped
mandrel
molded
infiltrated
zirconyl
nitrate
resulting
structure
dried
form
rigid
removed
placed
furnace
heated
air
temperature
600
driving
oxidizing
thereafter
950
250
fuse
nexi
matrix
produced
self-supporting
readily
machined
final
dimensions
additional
heating
1800
improves
structural
rigidity
zirconia fibers
vacuum molding
additional heat
thermal insulation
stabilized zirconia
aqueous slurry
partially stabilized
desired configuration
highly pure
suitable configuration
rigid structure
final dimensions
desired final
suitably shaped
resulting structure
zirconia fiber
zirconia composite
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