Method for bonding thin film thermocouples to ceramics

Patent · Thu Dec 31 23:00:00 EST 1992

OSTI ID:868797

Kreider, Kenneth G ^[1]

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1. Potomac, MD

A method is provided for adhering a thin film metal thermocouple to a ceramic substrate used in an environment up to 700 degrees Centigrade, such as at a cylinder of an internal combustion engine. The method includes the steps of: depositing a thin layer of a reactive metal on a clean ceramic substrate; and depositing thin layers of platinum and a platinum-10% rhodium alloy forming the respective legs of the thermocouple on the reactive metal layer. The reactive metal layer serves as a bond coat between the thin noble metal thermocouple layers and the ceramic substrate. The thin layers of noble metal are in the range of 1-4 micrometers thick. Preferably, the ceramic substrate is selected from the group consisting of alumina and partially stabilized zirconia. Preferably, the thin layer of reactive metal is in the range of 0.015-0.030 micrometers (15-30 nanometers) thick. The preferred reactive metal is chromium. Other reactive metals may be titanium or zirconium. The thin layer of reactive metal may be deposited by sputtering in ultra high purity argon in a vacuum of approximately 2 milliTorr (0.3 Pascals).

• Research Organization: NATIONAL BUREAU OF STANDARDS
• DOE Contract Number: AI05-83OR21375
• Assignee: United States of America as represented by United States (Washington, DC)
• Patent Number(s): US 5215597
• OSTI ID: 868797
• Country of Publication: United States
• Language: English

Related Subjects

/136/
015-0
030
1-4
15-30
700
active metal
active metals
adhering
alloy
alloy form
alumina
approximately
argon
bond
bond coat
bonding
centigrade
ceramic
ceramic substrate
ceramics
chromium
clean
coat
combustion
combustion engine
consisting
cylinder
degrees
degrees centigrade
deposited
depositing
engine
environment
film
film metal
forming
internal
internal combustion
layer
layer serves
layers
legs
metal
metal layer
metals
method
micrometers
micrometers thick
millitorr
nanometers
noble
noble metal
partially
partially stabilized
pascals
platinum
platinum-10
preferably
preferred
provided
purity
purity argon
range
reactive
reactive metal
reactive metals
respective
rhodium
selected
serves
sputtering
stabilized
stabilized zirconia
steps
substrate
thermocouple
thermocouples
thick
titanium
ultra
vacuum
zirconia
zirconium