U.S. patent application number 10/073034 was filed with the patent office on 2003-08-14 for structure and manufacture of a heat sink with high heat transmission.
Invention is credited to Chen, Yung-Cheng, Huang, Chuan-Cheng, Tung, Chuan-Ching, Yeh, Jia-Jen.
Application Number | 20030150595 10/073034 |
Document ID | / |
Family ID | 32327256 |
Filed Date | 2003-08-14 |
United States Patent
Application |
20030150595 |
Kind Code |
A1 |
Chen, Yung-Cheng ; et
al. |
August 14, 2003 |
Structure and manufacture of a heat sink with high heat
transmission
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.
Inventors: |
Chen, Yung-Cheng; (Taoyuan
City, TW) ; Huang, Chuan-Cheng; (Taoyuan City,
TW) ; Tung, Chuan-Ching; (Taoyuan City, TW) ;
Yeh, Jia-Jen; (Taoyuan City, TW) |
Correspondence
Address: |
Loyalty Founder Enterprise Co., Ltd.
P. O. Box No. 6-57
Chung-Ho
Taipei
235
TW
|
Family ID: |
32327256 |
Appl. No.: |
10/073034 |
Filed: |
February 12, 2002 |
Current U.S.
Class: |
165/80.3 ;
165/905; 257/E23.099; 257/E23.109 |
Current CPC
Class: |
H01L 23/467 20130101;
F28F 21/084 20130101; H01L 23/3736 20130101; H01L 2924/0002
20130101; H01L 2924/0002 20130101; H01L 2924/00 20130101 |
Class at
Publication: |
165/80.3 ;
165/905 |
International
Class: |
F28F 007/00 |
Claims
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 40-3000 .mu.m.
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.
Description
BACKGROUND OF THE INVENTION
[0001] 1) Field of the Invention
[0002] 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.
[0003] 2) Description of the Prior Art
[0004] Accordingly, with continuously increased operating speed,
the power of a central process unit (CPU) of a computer 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 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 CPU of a
conventional computer has been gradually replaced by the copper
alloy with higher efficiency of heat transmission.
[0005] 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 with 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
[0006] Therefore, the primary objective of the present invention is
to use 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.
[0007] 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.
[0008] To enable a further understanding the structure and
objectives of the present invention, the brief description of the
drawings below is followed by the detailed description of the
preferred embodiment.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 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.
[0010] FIG. 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.
[0011] FIG. 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
[0012] The present invention of a 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
AlSi, AlSiCu, AlSiZn, AlSiMg, AlSiCuMg, AlGe, AlGeSi, AlCu, AlMn,
AlLi, AlSn and AlPb; the ceramic grains are grains of silicon
carbide with the size of 40-3000 .mu.m.
[0013] 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
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.
[0014] 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 the copper-made heat sink; furthermore, with
different contents of the ceramic grains, the heat transmission
coefficients 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 or 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.sup.3; to compare
with 8.6 g/cm.sup.3 of the conventional copper-made heat sink, the
weight can be reduced about 1/2 to 2/3; therefore, it meets the
requirements of the designing demands of a notebook computer even
more.
[0015] 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; 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.
[0016] 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.
* * * * *