US5310520A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Circuit system, a composite material for use therein, and a method of making the material
Assignee: Texas Instruments Inc
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Filing: 1993-01-29
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Granted: 1994-05-10
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Expires: 2013-01-29
Abstract
Abstract Discrete powder particles of copper 14 and INVAR 12 are mixed together in a container 16 and packed into a powder metal article. This article is hot vacuum degassed and vacuum sealed and then heated to temperature well below the sintering temperature of copper or INVAR. Immediately after heating the article, it is subjected to a high pressure, high strain force such as extrusion through a die thereby yielding a fully dense, strong composite material 10 with excellent combined thermal expansion and conductivity properties.
Inventors
- 👤 Sunil C. Jha
- 👤 James A. Forster
- 👤 Henry F. Breit
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 10:28
CPC Classifications
B; B22; B22F; B22F3/00; B22F3/20; B22F1/00; B22F1/09; C; C22; C22C; C22C9/00; H; H10; H10W; H10W40/00; H10W40/20; H10W40/25; H10W40/257
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
146 words
A method for making a thermal composite material for use in electronic circuit systems comprising: a) providing a first powder metal material of a low coefficient of thermal expansion; b) providing a second powder metal material of a high thermal conductivity; c) mixing said first powder material with said second powder material; d) packing said mixture into an article; e) heating said article to a temperature below the sintering temperature for either said first powder metal material or said second powder metal material for sufficient time to have uniform temperature throughout the article; and f) immediately subjecting said heated article to extrusion through a die having an area reduction ratio of at least 8 to 1 so as to impart a true strain to said compacted article of greater than 1.75, thereby yielding a fully dense composite material with excellent combined thermal expansion and conductivity properties.
Claim 2
Independent Claim
146 words
A method for making a thermal composite material for use in electronic circuit systems comprising: a) providing a first powder metal material of a low coefficient of thermal expansion; b) providing a second powder metal material of a high thermal conductivity; c) mixing said first powder material with said second powder material; d) packing said mixture into an article; e) heating said article to a temperature below the sintering temperature for either said first powder metal material or said second powder metal material for sufficient time to have uniform temperature throughout the article; and f) immediately subjecting said heated article to extrusion through a die having an area reduction ratio of at least 8 to 1 so as to impart a true strain to said compacted article of greater than 1.75, thereby yielding a fully dense composite material with excellent combined thermal expansion and conductivity properties.
Claim 3
Dependent Claim
22 words
The method of claim 1 wherein said first powder metal material of a low coefficient of thermal expansion is an iron-nickel alloy.
Claim 4
Dependent Claim
32 words
The method of claim 1 wherein second powder metal material of a high thermal conductivity is selected from the group consisting of essentially pure copper, essentially pure aluminum and high copper-silver alloys.
Claim 5
Dependent Claim
33 words
The method of claim 1 wherein said packing of said first and second powder materials is done in a container yielding a article having a density of at least 50% of theoretical density.
Claim 6
Dependent Claim
53 words
The method of claim 1 further including the step of hot vacuum degassing and sealing said article to a vacuum level of about at least 10 -4 Torr prior to heating said article to a temperature below the sintering temperature of either said first powder metal material or said second powder metal material.
Claim 7
Independent Claim
180 words
A method of making a thermal management composite material for use in electronic circuit systems comprising: a) providing a first iron-nickel alloy powder metal material of a low coefficient of thermal expansion; b) providing a second powder metal material of a high thermal conductivity; c) mixing said first and second powder materials to yield a homogeneous mixture; d) packing said homogeneous mixture in a container into an article having a porosity of less than 50 percent; e) hot vacuum degassing and sealing said article; f) heating said article to a temperature below the sintering temperature for either said first powder metal material or said second powder metal material for sufficient time to have uniform temperature throughout the article; and g) immediately extruding said heated article through a die having a reduction ratio of at least 8 to 1 so as to impart a true strain to said compacted article of greater than 1.75 with an extrusion ram speed of at least 1 foot per minute thereby yielding a fully dense composite material with excellent combined thermal expansion and conductivity properties.
Claim 8
Independent Claim
180 words
A method of making a thermal management composite material for use in electronic circuit systems comprising: a) providing a first iron-nickel alloy powder metal material of a low coefficient of thermal expansion; b) providing a second powder metal material of a high thermal conductivity; c) mixing said first and second powder materials to yield a homogeneous mixture; d) packing said homogeneous mixture in a container into an article having a porosity of less than 50 percent; e) hot vacuum degassing and sealing said article; f) heating said article to a temperature below the sintering temperature for either said first powder metal material or said second powder metal material for sufficient time to have uniform temperature throughout the article; and g) immediately extruding said heated article through a die having a reduction ratio of at least 8 to 1 so as to impart a true strain to said compacted article of greater than 1.75 with an extrusion ram speed of at least 1 foot per minute thereby yielding a fully dense composite material with excellent combined thermal expansion and conductivity properties.
Claim 9
Dependent Claim
23 words
The method of claim 6 wherein said extruding of said heated article imparts a true strain to said article of greater than 1.75.
Claim 10
Independent Claim
201 words
A method of making a thermal management composite material for use in electronic circuit systems comprising: a) providing a first iron-nickel alloy powder metal material of a low coefficient of thermal expansion; b) providing a second powder metal material of a high thermal conductivity; c) mixing said first and second powder materials to yield a homogeneous mixture; d) packing said homogeneous mixture in a container into an article having a porosity of less than 50 percent; e) hot vacuum degassing and sealing said article; f) heating said article to a temperature below the sintering temperature for either said first powder metal material or said second powder metal material for sufficient time to have uniform temperature throughout the article; g) immediately extruding said heated article through a die having a reduction ratio of at least 8 to 1 with an extrusion ram speed of at least 1 foot per minute thereby yielding a fully dense composite material with excellent combined thermal expansion and conductivity properties; and h) preferentially etching the surface of the fully dense composite material to remove only one of the first powder metal material or the second powder metal material thereby yielding a porous surface to enhance bonding characteristics.
Claim 11
Independent Claim
201 words
A method of making a thermal management composite material for use in electronic circuit systems comprising: a) providing a first iron-nickel alloy powder metal material of a low coefficient of thermal expansion; b) providing a second powder metal material of a high thermal conductivity; c) mixing said first and second powder materials to yield a homogeneous mixture; d) packing said homogeneous mixture in a container into an article having a porosity of less than 50 percent; e) hot vacuum degassing and sealing said article; f) heating said article to a temperature below the sintering temperature for either said first powder metal material or said second powder metal material for sufficient time to have uniform temperature throughout the article; g) immediately extruding said heated article through a die having a reduction ratio of at least 8 to 1 with an extrusion ram speed of at least 1 foot per minute thereby yielding a fully dense composite material with excellent combined thermal expansion and conductivity properties; and h) preferentially etching the surface of the fully dense composite material to remove only one of the first powder metal material or the second powder metal material thereby yielding a porous surface to enhance bonding characteristics.
Claim 12
Dependent Claim
44 words
The method of claim 6 wherein said container holding said first and said second powder metal material is made from a material having a high thermal conductivity and after being subjected to extrusion forms an at least partial surface coating for the composite material.
Claim 13
Dependent Claim
29 words
The method of claim 6 wherein said step of hot vacuum degassing and sealing of said compacted article yields a vacuum level of about at least 10 -4 Torr.
Claim 14
Dependent Claim
147 words
A thermal management composite material which is the product of the process comprising the steps of: a) providing a first powder metal material of a low coefficient of thermal expansion; b) providing a second powder metal material of a high thermal conductivity; c) mixing said first powder metal with said second powder metal; d) packing said mixture into an article; e) heating said article to a temperature below the sintering temperature for either said first powder metal material or said second powder metal material for sufficient time to have uniform temperature throughout the article; and f) immediately subjecting said heated article to extrusion through a die having an area reduction ratio of at least 8 to 1 so as to impart a true strain to said compacted article of greater than 1.75 thereby yielding a fully dense composite material with excellent combined thermal expansion and conductivity properties.
Claim 15
Dependent Claim
147 words
A thermal management composite material which is the product of the process comprising the steps of: a) providing a first powder metal material of a low coefficient of thermal expansion; b) providing a second powder metal material of a high thermal conductivity; c) mixing said first powder metal with said second powder metal; d) packing said mixture into an article; e) heating said article to a temperature below the sintering temperature for either said first powder metal material or said second powder metal material for sufficient time to have uniform temperature throughout the article; and f) immediately subjecting said heated article to extrusion through a die having an area reduction ratio of at least 8 to 1 so as to impart a true strain to said compacted article of greater than 1.75 thereby yielding a fully dense composite material with excellent combined thermal expansion and conductivity properties.
Claim 16
Dependent Claim
57 words
The thermal management composite material of claim 11 further including the step of hot vacuum degassing and sealing said compacted article to a vacuum level of about at least 10 -4 Torr prior to heating said article to a temperature below the sintering temperature of either said first powder metal material or said second powder metal material.
Claim 17
Dependent Claim
51 words
The thermal management composite material of claim 11 in which mixing said first powder material and said second powder metal is done in a container made from a material having a high thermal conductivity and after being subjected to extrusion forms an at least partial surface coating for the composite material.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-05-09 | 1997-11-08 | 1998-05-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-05-09 | 2001-11-08 | 2002-05-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-05-09 | 2005-11-08 | 2006-05-10 | $7700.00 | Window Closed / Lapsed |