CA2379600A1 - Structure and manufacture of a heat sink with high heat transmission - Google Patents
Structure and manufacture of a heat sink with high heat transmission Download PDFInfo
- Publication number
- CA2379600A1 CA2379600A1 CA002379600A CA2379600A CA2379600A1 CA 2379600 A1 CA2379600 A1 CA 2379600A1 CA 002379600 A CA002379600 A CA 002379600A CA 2379600 A CA2379600 A CA 2379600A CA 2379600 A1 CA2379600 A1 CA 2379600A1
- Authority
- CA
- Canada
- Prior art keywords
- heat sink
- aluminum alloy
- grains
- high heat
- ceramic
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
- F28F21/00—Constructions of heat-exchange apparatus characterised by the selection of particular materials
- F28F21/08—Constructions of heat-exchange apparatus characterised by the selection of particular materials of metal
- F28F21/081—Heat exchange elements made from metals or metal alloys
- F28F21/084—Heat exchange elements made from metals or metal alloys from aluminium or aluminium alloys
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/34—Arrangements for cooling, heating, ventilating or temperature compensation ; Temperature sensing arrangements
- H01L23/36—Selection of materials, or shaping, to facilitate cooling or heating, e.g. heatsinks
- H01L23/373—Cooling facilitated by selection of materials for the device or materials for thermal expansion adaptation, e.g. carbon
- H01L23/3736—Metallic materials
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/34—Arrangements for cooling, heating, ventilating or temperature compensation ; Temperature sensing arrangements
- H01L23/46—Arrangements for cooling, heating, ventilating or temperature compensation ; Temperature sensing arrangements involving the transfer of heat by flowing fluids
- H01L23/467—Arrangements for cooling, heating, ventilating or temperature compensation ; Temperature sensing arrangements involving the transfer of heat by flowing fluids by flowing gases, e.g. air
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
- H01L2924/0001—Technical content checked by a classifier
- H01L2924/0002—Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Power Engineering (AREA)
- General Physics & Mathematics (AREA)
- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- Chemical & Material Sciences (AREA)
- Materials Engineering (AREA)
- Thermal Sciences (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Manufacture Of Alloys Or Alloy Compounds (AREA)
- Cooling Or The Like Of Semiconductors Or Solid State Devices (AREA)
Abstract
The present invention of a structure and manufacture of a heat sink with high heat transmission mainly uses a shear stress caused by stirring to break or crush the solidified arborescent primary crystal at a solid/liquid two-phase area of a aluminum alloy to form a slag fluid with ball-filled solid crushed grit; then ceramic grains are added in and dispersed by the solid grains scattered in the liquid-phase metal; through continuous stirring, the aluminum alloy becomes a fine mixed fluid of ceramic and aluminum alloy without arborescent forms; finally, the external configuration of a heat sink is accomplished through directly compression casting by using the special nature of the aluminum alloy to mold the entire heat sink and to enhance the effect of heat dissipation of the heat sink of the same structure through the high heat transmission efficiency of the ceramic grains.
Description
Structure and Manufacture of a Heat Sink with High Heat Transmission BACKGROUND OF THE INVENTION
I) FIELD OF THE INVENTION
The present invention of a structure and manufacture of a heat sink with high heat transmission aims to provide; a heat sink with light weight and heat transmission higher' than that of a conventional copper%aluminum alloy to accomplish the external configuration of various heat sinks through direct compression casting for dissipating high heat sources in a central process unit of a computer.
I) FIELD OF THE INVENTION
The present invention of a structure and manufacture of a heat sink with high heat transmission aims to provide; a heat sink with light weight and heat transmission higher' than that of a conventional copper%aluminum alloy to accomplish the external configuration of various heat sinks through direct compression casting for dissipating high heat sources in a central process unit of a computer.
2) DESCRIPTION OF THE PRIOR ART
Accordingly, with continuously increased operating speed, the power of a central process unit (CPU) of a <;omputer is also enhanced; at the same time, more heat sources are generated; the common heat sink applied to the CPU mainly uses a heat transmission action to dissipate the heat source thereof; therefore, heat fins are 1.'i properly spaced on the main body of the heat sink; the disposition of heat fins increases the air contact area so as to achieve the release of heat sources;
therefore, basically, the effect of heat dissipation depends on the heat transmission efficiency of the main body of the heat sink; as a result, the heat sink with an aluminum alloy main body used for a C:PU of a conventional computer has been gradually replaced by the 2C~ copper alloy with higher efficiency of heat transmission.
However, although the main body of the conventional heat sinks can be processed into various external configurations through drawing or extruding the copper/aluminum alloy, with limited efficiency of heat transmission of the structure thereof, it fails to meet the heat dissipation demands of a CPU wwith higher operating speed; more especially, in spite: of having heat transmission efficiency better than the aluminum alloy, the specific gravity of the entire heat sink of copper alloy is higher than that of the heat sink of aluminum alloy and that does not meet the requirements of a lightweight computer.
SUMMARY OF THE INVENTION
Therefore, the primary objective of the present invention is to use a shear stress caused by stirnng to break or crush the solidified arborescent primary crystal at a solid/liquid two-phase area of a aluminum alloy to form a slag fluid with ball-filled solid crushed grit; then ceramic gxains are added in and dispersed by the solid grains scattered in the liquid-phase metal; through continuous stirring, the aluminum alloy 1 ~~ becomes a fine mixed fluid of ceramic and aluminum alloy without arborescent forms;
finally, the external configuration of a heat sink is accomplished through directly compression casting by using the special nature of the aluminum alloy to mold the entire heat sink and to enhance the effect of heat dissipation of the heat sink of the same structure through the high heat transmission efficiency of the ceramic grains.
Another objective of the present invention is to mix a proper ratio of ceramic grains into the aluminum alloy for tremendously reducing the mass of the entire heat sink so as to meet the requirements of the designing demands of the lightweight computer even more.
To enable a further understanding the structure and objectives of the present invention, the brief description of the drawings below is follawed by the detailed description of the preferred embodiment.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 illustrates the tested result obtained by simulating a desk-top computer using the same 80 watt heat source for the conventional copper-made heat sink and the heat sink of the present invention.
Figure 2 illustrates the tested result obtained by simulating a notebook computer using the same 35 watt heat source for the conventional copper-made heat sink and the heat sink of the present invention.
Figure 3 is a cross reference table of coefficients of the heat drag obtained through the experiments of the conventional copper-made heat sink and the heat sink of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention of s, structure and manufacture of a heat sink with high heat transmission has the entire heat sink thereof manufactured into various almost net shapes according to the need of the practical application; furthermore, ceramic grains in a proper ratio are mixed into the aluminum alloy of a main body of the entire structure so as to use the special nature of the aluminum alloy to mold the entire heat sink and to enhance the effect of heat dissipation of the heat sink of the same structure through the high heat transmission efficiency of the ceramic grains; wherein, the aluminum alloy is composed by freely grouping AISi, AISiC'.u, AISiZn, AISiMg, AISiCuMg, AIGe, AIGeSi, Al<:u" AIMn, AILi, AISn and AIPb; the ceramic grains are grains of silicon carbide with the size of 4l)-3000um.
Furthermore, the manufacturing of the entire heat sink uses a shear stress caused by stirring to break or crush the solidified arborescent primary crystal at a solid/liquid two-phase area of a aluminum alloy to form a slag fluid with ball-filled solid crushed grit; then ceramic grains are, added in and dispersed by the solid grains scattered in the liquid-phase metal; through continuous stirnng, the aluminum alloy becomes a fine mixed fluid of ceramic and aluminum alloy without arborescent forms;
finally, the external configuration of a heat sink is accomplished through directly compression casting.
In the present invention, since a proper ratio of ceramic grains are mixed into the aluminum alloy, the high heat transmission efficiency of the ceramic grains is used to enhance the heat dissipation effect of the structure of the same form;
as indicated in FIGS. 1 to 3, the experimental comparison between the finished sample of the present invention and a conventional copper-made heat sink, the heat transmission efficiency of the heat sink of the present invention is 485 W/mK
higher than the magnitude of 4000 W'/mK of th<: copper-made heat sink; furthermore, with different contents of the ceramic grains, the heat transmission caefficients of the heat sink of the present invention are between 150 and 485 W/mK and that can be applied to a central process unit (CPU) with heat source above 85 W c~r speed of 2.2 GHz;
however, the heat transmission coefficient of the conventional copper-made heat sink is only 400 W/mK and that can only be used for a CPU with heat source of 80 W
at the most; more especially, with different contents of the ceramic grains, the density of the heat sink of the present invention is between 2.7 and 3.5 g/cm'; to compare with 8.6 g/cm' of the conventional copper-made heat sink, the weight can be reduced about to Z~3; therefore, it meets the requirements of the designing demands of a notebook computer even more.
The present invention of a structure and manufacture of a heat sink with high heat transmission mainly uses a shear strews caused by stirring to break or crush the 1:5 solidified arborescent primary crystal at a solid/liquid two-phase area of a aluminum alloy to foam a slag fluid with ball-filled solid crushed grit; then ceramic grains are added in and dispersed by the solid grains scattered in the liquid-phase metal; through continuous stirring, the aluminum alloy becomes a fine mixed fluid of ceramic and aluminum alloy without arboresc:ent forms; finally, the external configuration of a heat sink is accomplished through directly compression casting by using the special 'i nature of the aluminum alloy to mold the entire heat sink and to enhance the effect of heat dissipation of the heat sink of the same structure through the high heat transmission efficiency of the ceramic grains; therefore, the present invention provides another structure and manufacture of a heat sink with higher heat transmission and is lawfully submitted to the patent application hereby.
It is of course to be understood that the embodiment described herein is merely illustrative of the principles of the invention and that a wide variety of modifications thereto may be effected by persons skilled in the art without departing from the spirit and scope of the invention as set forth in the following claims.
:~ a
Accordingly, with continuously increased operating speed, the power of a central process unit (CPU) of a <;omputer is also enhanced; at the same time, more heat sources are generated; the common heat sink applied to the CPU mainly uses a heat transmission action to dissipate the heat source thereof; therefore, heat fins are 1.'i properly spaced on the main body of the heat sink; the disposition of heat fins increases the air contact area so as to achieve the release of heat sources;
therefore, basically, the effect of heat dissipation depends on the heat transmission efficiency of the main body of the heat sink; as a result, the heat sink with an aluminum alloy main body used for a C:PU of a conventional computer has been gradually replaced by the 2C~ copper alloy with higher efficiency of heat transmission.
However, although the main body of the conventional heat sinks can be processed into various external configurations through drawing or extruding the copper/aluminum alloy, with limited efficiency of heat transmission of the structure thereof, it fails to meet the heat dissipation demands of a CPU wwith higher operating speed; more especially, in spite: of having heat transmission efficiency better than the aluminum alloy, the specific gravity of the entire heat sink of copper alloy is higher than that of the heat sink of aluminum alloy and that does not meet the requirements of a lightweight computer.
SUMMARY OF THE INVENTION
Therefore, the primary objective of the present invention is to use a shear stress caused by stirnng to break or crush the solidified arborescent primary crystal at a solid/liquid two-phase area of a aluminum alloy to form a slag fluid with ball-filled solid crushed grit; then ceramic gxains are added in and dispersed by the solid grains scattered in the liquid-phase metal; through continuous stirring, the aluminum alloy 1 ~~ becomes a fine mixed fluid of ceramic and aluminum alloy without arborescent forms;
finally, the external configuration of a heat sink is accomplished through directly compression casting by using the special nature of the aluminum alloy to mold the entire heat sink and to enhance the effect of heat dissipation of the heat sink of the same structure through the high heat transmission efficiency of the ceramic grains.
Another objective of the present invention is to mix a proper ratio of ceramic grains into the aluminum alloy for tremendously reducing the mass of the entire heat sink so as to meet the requirements of the designing demands of the lightweight computer even more.
To enable a further understanding the structure and objectives of the present invention, the brief description of the drawings below is follawed by the detailed description of the preferred embodiment.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 illustrates the tested result obtained by simulating a desk-top computer using the same 80 watt heat source for the conventional copper-made heat sink and the heat sink of the present invention.
Figure 2 illustrates the tested result obtained by simulating a notebook computer using the same 35 watt heat source for the conventional copper-made heat sink and the heat sink of the present invention.
Figure 3 is a cross reference table of coefficients of the heat drag obtained through the experiments of the conventional copper-made heat sink and the heat sink of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention of s, structure and manufacture of a heat sink with high heat transmission has the entire heat sink thereof manufactured into various almost net shapes according to the need of the practical application; furthermore, ceramic grains in a proper ratio are mixed into the aluminum alloy of a main body of the entire structure so as to use the special nature of the aluminum alloy to mold the entire heat sink and to enhance the effect of heat dissipation of the heat sink of the same structure through the high heat transmission efficiency of the ceramic grains; wherein, the aluminum alloy is composed by freely grouping AISi, AISiC'.u, AISiZn, AISiMg, AISiCuMg, AIGe, AIGeSi, Al<:u" AIMn, AILi, AISn and AIPb; the ceramic grains are grains of silicon carbide with the size of 4l)-3000um.
Furthermore, the manufacturing of the entire heat sink uses a shear stress caused by stirring to break or crush the solidified arborescent primary crystal at a solid/liquid two-phase area of a aluminum alloy to form a slag fluid with ball-filled solid crushed grit; then ceramic grains are, added in and dispersed by the solid grains scattered in the liquid-phase metal; through continuous stirnng, the aluminum alloy becomes a fine mixed fluid of ceramic and aluminum alloy without arborescent forms;
finally, the external configuration of a heat sink is accomplished through directly compression casting.
In the present invention, since a proper ratio of ceramic grains are mixed into the aluminum alloy, the high heat transmission efficiency of the ceramic grains is used to enhance the heat dissipation effect of the structure of the same form;
as indicated in FIGS. 1 to 3, the experimental comparison between the finished sample of the present invention and a conventional copper-made heat sink, the heat transmission efficiency of the heat sink of the present invention is 485 W/mK
higher than the magnitude of 4000 W'/mK of th<: copper-made heat sink; furthermore, with different contents of the ceramic grains, the heat transmission caefficients of the heat sink of the present invention are between 150 and 485 W/mK and that can be applied to a central process unit (CPU) with heat source above 85 W c~r speed of 2.2 GHz;
however, the heat transmission coefficient of the conventional copper-made heat sink is only 400 W/mK and that can only be used for a CPU with heat source of 80 W
at the most; more especially, with different contents of the ceramic grains, the density of the heat sink of the present invention is between 2.7 and 3.5 g/cm'; to compare with 8.6 g/cm' of the conventional copper-made heat sink, the weight can be reduced about to Z~3; therefore, it meets the requirements of the designing demands of a notebook computer even more.
The present invention of a structure and manufacture of a heat sink with high heat transmission mainly uses a shear strews caused by stirring to break or crush the 1:5 solidified arborescent primary crystal at a solid/liquid two-phase area of a aluminum alloy to foam a slag fluid with ball-filled solid crushed grit; then ceramic grains are added in and dispersed by the solid grains scattered in the liquid-phase metal; through continuous stirring, the aluminum alloy becomes a fine mixed fluid of ceramic and aluminum alloy without arboresc:ent forms; finally, the external configuration of a heat sink is accomplished through directly compression casting by using the special 'i nature of the aluminum alloy to mold the entire heat sink and to enhance the effect of heat dissipation of the heat sink of the same structure through the high heat transmission efficiency of the ceramic grains; therefore, the present invention provides another structure and manufacture of a heat sink with higher heat transmission and is lawfully submitted to the patent application hereby.
It is of course to be understood that the embodiment described herein is merely illustrative of the principles of the invention and that a wide variety of modifications thereto may be effected by persons skilled in the art without departing from the spirit and scope of the invention as set forth in the following claims.
:~ a
Claims (6)
1. A heat sink with high heat transmission is characterized that the entire heat sink thereof is manufactured into various almost net shapes according to the need of the practical application; furthermore, ceramic grains are mixed in a proper ratio into the aluminum alloy of a main body of the entire structure so as to use the special nature of the aluminum alloy to mold the entire heat sink and to enhance the effect of heat dissipation of the heat sink of the same structure through the high heat transmission efficiency of the ceramic grains
2. The present invention of a heat sink with high heat transmission according to Claim 1, wherein, the aluminum alloy is composed by freely grouping AlSi, AlSiCu, AlSiZn, AlSiMg, AlSiCuMg, AlGe, AlGeSi, AlCu, AlMn, AlLi, AlSn and AlPb.
3. The present invention of a heat sink with high heat transmission according to Claim 1, wherein, the ceramic grains are grains of silicon carbide.
4. The present invention of a heat sink with high heat transmission according to Claim 1, wherein, the sizes of grains of silicon carbides are preferred to be between 40-3000µm.
5. The present invention of a heat sink with high heat transmission according to Claim 1, wherein, the ceramic grains occupy weight ratio 0.5-80% of the entire heat sink.
6. A structure and manufacture of a heat sink with high heat transmission mainly uses a shear stress caused by stirring to break or crush the solidified arborescent primary crystal at a solid/liquid two-phase area of a aluminum alloy to form a slag fluid with ball-filled solid crushed grit; then ceramic grains are added in and dispersed by the solid grains scattered in the liquid-phase metal; through continuous stirring, the aluminum alloy becomes a fine mixed fluid of ceramic and aluminum alloy without arborescent forms; finally, the external configuration of a heat sink is accomplished through directly compression casting.
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/073,034 US20030150595A1 (en) | 2002-02-12 | 2002-02-12 | Structure and manufacture of a heat sink with high heat transmission |
CA002379600A CA2379600A1 (en) | 2002-02-12 | 2002-03-28 | Structure and manufacture of a heat sink with high heat transmission |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/073,034 US20030150595A1 (en) | 2002-02-12 | 2002-02-12 | Structure and manufacture of a heat sink with high heat transmission |
CA002379600A CA2379600A1 (en) | 2002-02-12 | 2002-03-28 | Structure and manufacture of a heat sink with high heat transmission |
Publications (1)
Publication Number | Publication Date |
---|---|
CA2379600A1 true CA2379600A1 (en) | 2003-09-28 |
Family
ID=32327256
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CA002379600A Abandoned CA2379600A1 (en) | 2002-02-12 | 2002-03-28 | Structure and manufacture of a heat sink with high heat transmission |
Country Status (2)
Country | Link |
---|---|
US (1) | US20030150595A1 (en) |
CA (1) | CA2379600A1 (en) |
Families Citing this family (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6667191B1 (en) * | 2002-08-05 | 2003-12-23 | Asat Ltd. | Chip scale integrated circuit package |
JP4532422B2 (en) * | 2006-03-02 | 2010-08-25 | 古河電気工業株式会社 | Heat sink with centrifugal fan |
CN102135117A (en) * | 2010-01-23 | 2011-07-27 | 富准精密工业(深圳)有限公司 | Centrifugal fan |
CN104205217B (en) * | 2012-03-22 | 2017-10-13 | 富士电机株式会社 | The magnetic recording media of HAMR |
CN108595887B (en) * | 2018-05-10 | 2022-10-25 | 南京航空航天大学 | Simulation calculation and prediction method for abrasion evolution of polycrystalline CBN (cubic boron nitride) abrasive particles |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5222542A (en) * | 1988-11-10 | 1993-06-29 | Lanxide Technology Company, Lp | Method for forming metal matrix composite bodies with a dispersion casting technique |
US5513688A (en) * | 1992-12-07 | 1996-05-07 | Rheo-Technology, Ltd. | Method for the production of dispersion strengthened metal matrix composites |
US5706999A (en) * | 1995-11-28 | 1998-01-13 | Hughes Electronics | Preparation of a coated metal-matrix composite material |
US5981085A (en) * | 1996-03-21 | 1999-11-09 | The Furukawa Electric Co., Inc. | Composite substrate for heat-generating semiconductor device and semiconductor apparatus using the same |
US6245442B1 (en) * | 1997-05-28 | 2001-06-12 | Kabushiki Kaisha Toyota Chuo | Metal matrix composite casting and manufacturing method thereof |
JP3041421B1 (en) * | 1999-02-02 | 2000-05-15 | 広島大学長 | Ceramic reinforced metal matrix composite and method for producing the same |
-
2002
- 2002-02-12 US US10/073,034 patent/US20030150595A1/en not_active Abandoned
- 2002-03-28 CA CA002379600A patent/CA2379600A1/en not_active Abandoned
Also Published As
Publication number | Publication date |
---|---|
US20030150595A1 (en) | 2003-08-14 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
EEER | Examination request | ||
FZDE | Discontinued |