CN1785571A - Combining method of copper and aluminium alloy - Google Patents
Combining method of copper and aluminium alloy Download PDFInfo
- Publication number
- CN1785571A CN1785571A CN200410077431.4A CN200410077431A CN1785571A CN 1785571 A CN1785571 A CN 1785571A CN 200410077431 A CN200410077431 A CN 200410077431A CN 1785571 A CN1785571 A CN 1785571A
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- China
- Prior art keywords
- copper
- aluminium alloy
- combining method
- constant temperature
- aluminium
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
- C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
- C22F1/04—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of aluminium or alloys based thereon
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
- C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
- C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
- C22F1/08—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of copper or alloys based thereon
Abstract
A method for binding two CuAl alloy materials includes such steps as treating the surfaces to be bound, closing two surface tightly, putting them in heater, fast heating, holding the temp constant for alloy diffusion, and natural cooling.
Description
[technical field]
The invention relates to a kind of associated methods of albronze material, particularly a kind ofly can overcome its interface impedance, reduce the associated methods of the albronze material of interface thermal resistance.
[background technology]
The copper aluminium material material has purposes more widely in industrial production, being connected in being connected of dissimilar metal of copper and aluminium has considerable status, and many albronze combination technologies are arranged in the market.The most typical example for the albronze combination technology is the radiator process technique that is used for cool electronic assemblies.
Central processing unit (CPU) is a highdensity pyrotoxin, will spread heat to a bigger area be relended the forced convertion effect that helps fan it is dispersed in the air earlier, reaches the heat radiation purpose.Heat is dispersed into fin surface from core cpu, is a heat transfer process.Fin selects for use the material of high thermal conductivity helpful to improving heat conduction efficiency, thermal conductivity factor as aluminium is 735KJ/ (M.H.K), the thermal conductivity factor of copper is 1386KJ/ (M.H.K), and when all other conditions were all identical, the heat that copper conducted in the unit interval was the nearly twice of aluminium.As seen use aluminum alloy heat sink instead copper manufacturing, will have a very considerable lifting to the conduction velocity of heat, certain so just have obvious advantageous effects to the heat of CPU high concentration.But, need also to consider that the proportion of copper is bigger than aluminium, will not meet the requirement of fin weight limits; The hardness of copper is not as aluminium alloy, and some machining property is not as aluminium, as profile groove etc.; The fusing point of copper is high more a lot of than aluminium, is unfavorable for extrusion molding or the like problem.
So industry in conjunction with application, is utilized the high thermal conductivity coefficient characteristics of copper with copper, aluminium, heat is conducted to the fin of aluminium material, the convection action by fan is distributed in the air again.Both guaranteed that its weight did not exceed standard, but volume production has again also obtained certain enhancing efficiency.
Present industry is no matter be the manufacturing that is applied to radiator, or other use, and its albronze combination the most commonly used has welding, screw closure, mechanical type pressing or the like.
Welding method system employing fusing point, is higher than under the temperature of scolder fusing point being lower than the mother metal fusing point as scolder than the low-melting metal material of mother metal, utilizes the wetting mother metal of liquid solder, fills the play movement, and condensation forms the welding method of firm engagement interface then.Master operation has: the material pre-treatment, assemble, add operations such as thermal weld, cooling, post processing.Welding manner commonly used is soldering, the aluminium surface can form the highly stable oxide layer (AL2O3) of one deck in air, it is higher to make copper and aluminium welding connect difficulty, this is the biggest factor that hinders welding, must or adopt chemical method that it is removed the back and electroplates one deck nickel or the metal of other easy welding with its removal, copper aluminium could weld together smoothly like this.But the product that employing copper and aluminium welding in the market connects is the most serious is exactly that rate of deposition is low or quality is unstable, thereby its interface thermal resistance is higher.
The screw closure method is to use the high-performance heat-conducting medium between aluminium and copper material, applies the tight back of defeating of 80Kgf and with screw it is locked, and the effect that its interface thermal resistance and copper and aluminium welding connect is suitable.This method is subjected to the flatness of heat-conducting medium, faying face and the factors such as torsion of screw, thereby there is the serious higher problem of interface thermal resistance equally in it.
Mechanical type pressing mode is that aluminium and copper material are pressed together by mechanical mode, because aluminium has ductility, so copper can combine with aluminium matter at normal temperatures, for example, aluminum material is provided with a cylinder hole, one copper material is cylindrical, its slightly larger in diameter is in the diameter of this aluminium matter circular hole, this copper post is squeezed in this aluminium matter hole mechanically, this mode also be more considerable in conjunction with effect, but have a fatal shortcoming be exactly copper in the process that is pressed into the aluminium hole, the aluminium internal surface of hole is easily by the copper scratch, have a strong impact on pyroconductivity, still have the high problem of interface thermal resistance.
Enhancement mode technology as the aluminium extrusion technology, though copper aluminium combination technology has effectively solved above-mentioned problem, but because there is serious interface impedance problems exactly in the greatest problem of copper aluminium combination technology, if can not head it off on the technology, finished product effect even can be not so good as full aluminium extruded product so.
[summary of the invention]
Technical problem to be solved by this invention is to provide a kind of combining method of copper and aluminium alloy that significantly reduces the interface thermal resistance by heat treatment mode.
The present invention will solve to such an extent that technical problem is achieved through the following technical solutions: combining method of copper and aluminium alloy of the present invention mainly may further comprise the steps: (1) material surface is handled, and respectively leveling is carried out on the surface of the desire combination of albronze material; (2) charging, surface-treated albronze material is positioned in the heater, and the surface that its desire is engaged relatively closely reclines; (3) heated constant temperature is handled, and albronze material heating device will be housed begin heating rapidly and constant temperature processing, makes the albronze material engage the interface place and produces a kind of diffusion alloy, and it is tight to make that the albronze material engages interface; (4) cooling is carried out the nature cooling with the finished product that has engaged in this heater; (5) discharging is taken out chilled finished product in this heater, obtain final product, if any waste product it is returned above-mentioned (2) step and carries out heavy industry.Wherein the atmosphere in this device is the protective atmosphere environment of anti-oxidation.
Compared with prior art, because combining method of copper and aluminium alloy of the present invention mainly is that the albronze material is heat-treated, can be not influential in structure and function aspects to the structural design of product itself; Need not do too cataclysm to production line originally aspect processing procedure and the cost, only need to adjust a little to get final product, not need too high equipment cost, the established technology cost is low, can be applicable to waste product heavy industry aspect simultaneously, significantly reduces manufacturing cost; The interface place of albronze material produces a kind of diffusion alloy, is unique processing procedure that fully reaches copper aluminium physical bond, and the mode that is formed alloy phase by interface reduces thermal resistance, significantly improves heat conductivity.
With reference to the accompanying drawings, the invention will be further described in conjunction with the embodiments.
[description of drawings]
Fig. 1 is the flow chart of the key step of combining method of copper and aluminium alloy of the present invention.
Fig. 2 is that the albronze material of combining method of copper and aluminium alloy of the present invention is in conjunction with schematic diagram.
Fig. 3 (a) to (d) is before the heat treatment of four groups of test piece A, B, C, D and respectively gets relatively coordinate diagram of the thermal resistivity of five test pieces after through heat treatment in 1,2,3,4 hour respectively.
Fig. 4 is the thermal resistivity coordinate diagram relatively of getting before and after the heat treatment of A, the B of Fig. 3 (a) to the mean value of (d), C, four groups of test pieces of D.
[specific embodiment]
Combining method of copper and aluminium alloy of the present invention mainly be by heat treatment mode overcome the albronze material in conjunction with the time the interface impedance problems, thereby significantly reduce the interface thermal resistance, promote heat transfer property.
But this combining method of copper and aluminium alloy generally use equipment is the heater of Fast Heating, heating furnace for example, and this heating furnace heats from the periphery by resistance wire, and maximum temperature can reach 1200 ℃, and the internal material of heating furnace is a pottery.Albronze material of the present invention comprises copper (Cu) material (fine copper or copper alloy) and aluminium alloy (Al) material (fine aluminium or aluminium alloy).
Fig. 1 is the flow chart of the key step of combining method of copper and aluminium alloy of the present invention, and Fig. 2 is that the albronze material of combining method of copper and aluminium alloy of the present invention is in conjunction with schematic diagram.This combining method of copper and aluminium alloy mainly may further comprise the steps:
(1) material surface is handled, planarizing process is carried out on the surface of the desire combination of albronze material, make its surface roughness the smaller the better, for example with albronze material surface Electrolyzed Processing or chemical grinding, clean the greasy dirt of albronze material surface more respectively by ethanol, acetone etc., remove its oxide layer by the vibration of ultrasonic wave method then;
(2) charging will be positioned in the heating furnace through surface-treated albronze material, its surface of desiring combination be reclined relatively, and give certain stress from the relative outside;
(3) heated constant temperature is handled, to assemble albronze material heating stove begins to be heated to rapidly about 330-420 ℃, and constant temperature was handled 1-4 hour, this moment since the albronze material be stressed and Temperature Influence under, its interface place produces a kind of diffusion alloy, for example: Al3Cu2, make that the joint interface of albronze material is tightr, thermal resistance also can significantly be reduced (as shown in Figure 2);
(4) cooling is carried out the nature cooling with the finished product of combination in stove;
(5) discharging is taken out chilled finished product in stove, obtain final product, if any waste product it is returned above-mentioned (2) step and carries out heavy industry.
Wherein, the required condition of each step is as follows:
One, surface roughness (Roughness, Ra) and processing conditions: before the albronze material heat treatment, the surface roughness of albronze material is very important, the surface is smooth more, contact (tight ness rating) is good more, and heat conductivility is better, so with its planarizing process, make its Roughness Surface on Control within the specific limits, thereby make the tight ness rating of albronze material before heat treatment reach good degree.
Two, stress (Stress, σ): in heat treatment process, the stress that utilizes both different coefficient of thermal expansion and contraction of copper and aluminium to produce, its interface is combined closely, owing to prevent the generation in diffusion cavity (Kirkendall effect) on the one hand, can avoid considering of its interface loose contact on the other hand as far as possible, preliminary experiment estimates that its stress is about 30Mpa, for accurate its stress intensity of control, so temperature controlling is very important.
Three, treatment temperature (Temperature, T): according to copper-aluminium phasor and the fusing point problem (the too high aluminium extruded material deformation that easily makes of temperature) of considering aluminium, temperature range depends on about 330-420 ℃, copper aluminium interface (for example: Al3Cu2) generates certain diffusion alloy in this temperature range, especially about 350-370 ℃, when soon this temperature was controlled at 360 ℃ of left and right sides, the diffusion alloy of its formation was even more ideal.The diffusion alloy of this generation can effectively reduce the thermal resistance problems of too that is caused because of the interface impedance, but the amount of this diffusion alloy can not be too much, and simultaneously this alloy-layer must be thin as much as possible, so the time of handling control is important parameters very.
Four, hold temperature time (time, t): in the preliminary experiment, distinguish 1,2,3 and 4 hour at said temperature constant temperature, thermal resistivity before and after its heat treatment changes comparing result shown in Fig. 3 (a) to (d), the thermal resistivity that can find to hold the test piece of temperature after 3 hours is starkly lower than the thermal resistivity of untreated test piece, but hold during high temperature the temperature time of a specified duration more, the test piece degree of oxidation is serious more, because oxide layer can have a strong impact on heat conductivility, for fear of the influence of oxide layer in processing procedure, the environment during processing is just extremely important.
Five, handle atmosphere: for fear of serious oxidation takes place in processing procedure, it is necessary handling under protective atmosphere.For example, the atmosphere of inside heating furnace satisfies the protective atmosphere of N2+H2.
From above feature as can be known, the heat treatment method of albronze combination of the present invention has following advantage:
(1) structure and function aspects: the structural design to product itself can be not influential, and can further promote the heat conductivity of product.
(2) processing procedure and cost aspect: need not do too cataclysm to product line originally, only need to adjust a little to get final product, not need too high equipment cost, can be applicable to waste product heavy industry aspect simultaneously, reduce manufacturing cost.
(3) fully reach the processing procedure of copper aluminium physical bond, the mode that is formed alloy phase by interface reduces thermal resistance, improves heat conductivity, estimates constant temperature and handles finished product after 3 hours and can increase heat conduction efficiency and slightly reach 20%.
Heat treatment experiment below in conjunction with copper aluminium material material (test piece) further specifies the present invention:
Test piece number A, B, C, D are respectively the heat treatment (330～420 ℃) through 1,2,3 and 4 hour, temperature in the stove are done once record in per 30 minutes, as shown in Table 1.Even if can find the test piece environment is not vacuum, but its variation of temperature difference can't be very big, is illustrated in the stove, its heating is uniform.
The temperature record of the heating furnace of table one, different time
Do the experimental analysis of thermal resistivity at the heat treatment test piece of four groups of different time conditions, each set condition is got five test pieces (test piece number be respectively 1,2,3,4,5), before heat treatment and after the heat treatment, do the analysis of thermal resistivity respectively, as Fig. 3 (a) to (d), among the figure, abscissa is test piece number, and ordinate is a thermal resistivity.Can find out obviously that from Fig. 3 (a) thermal resistivity after constant temperature heat treatment one hour is apparently higher than without heat treated test piece.Fig. 3 (b) is that the thermal resistivity through the Overheating Treatment test piece had the trend that is lower than without the heat treatment test piece as can be seen from Figure through the heat treated analysis of constant temperature in 2 hours.Then in Fig. 3 (c), find,, be starkly lower than thermal resistivity without the heat treatment test piece through the thermal resistivity of constant temperature heat treatment after three hours; But through the thermal resistivity after the constant temperature heat treatment in four hours but apparently higher than thermal resistivity without the heat treatment test piece, shown in Fig. 3 (d), this result's reason is that the amount of diffusion alloy of material interface is too much, and diffusion alloy is to being unfavorable for that reducing the thermal resistivity direction changes.Fig. 4 be sum up among Fig. 3 (a) to (d) without heat treatment and respectively through 1,2,3,4 hour heat treated test piece thermal resistivity and the comparison diagram of the thermal resistivity before and after the heat treatment of A, B after getting its mean value, C, four groups of test pieces of D.Among the figure, abscissa is each group number, and ordinate is a thermal resistivity.As can be seen from Fig. 4 through the reduced rate maximum of the test piece thermal resistivity after 3 hours, the tight ness rating of supposing A, B, C, four groups of test pieces of D is all good and basic identical, then obviously descend through the test piece thermal resistivity after the constant temperature heat treatment in 3 hours, this result is because two reasons:
1. because the temperature of aluminium extrusion is to carry out between 520～540 ℃, and test piece is at constant temperature after three hours, and the surface in aluminium hole may cause residual hard power to be eliminated because similar annealing effect takes place, and makes that copper aluminium tight ness rating is better, thereby reduces thermal resistivity.
2. with this understanding, its copper aluminium joint interface has enough time generations to diffuse to form certain stable phase alternately, thereby reduces thermal resistivity.
Claims (10)
1. combining method of copper and aluminium alloy may further comprise the steps: (1) material surface is handled, and respectively leveling is carried out on the surface of the desire combination of albronze material; (2) charging, surface-treated albronze material is positioned in the heater, and the surface that its desire is engaged relatively closely reclines; (3) heated constant temperature is handled, and albronze material heating device will be housed begin heating rapidly and constant temperature processing, makes the albronze material engage the interface place and produces a kind of diffusion alloy, and it is tight to make that the albronze material engages interface; (4) cooling is carried out the nature cooling with the finished product that has engaged in this heater; (5) discharging is taken out chilled finished product in this heater, obtain final product.
2. combining method of copper and aluminium alloy as claimed in claim 1 is characterized in that: described diffusion alloy is Al
3Cu
2
3. combining method of copper and aluminium alloy as claimed in claim 1 is characterized in that: the atmosphere in the described heater is the protective atmosphere environment of anti-oxidation.
4. combining method of copper and aluminium alloy as claimed in claim 3 is characterized in that: described protective atmosphere is for satisfying N
2+ H
2Protective atmosphere.
5. combining method of copper and aluminium alloy as claimed in claim 1 is characterized in that: described constant temperature temperature ranges is about 330-420 ℃.
6. combining method of copper and aluminium alloy as claimed in claim 5 is characterized in that: described constant temperature treatment temperature is about 350-370 ℃.
7. combining method of copper and aluminium alloy as claimed in claim 6 is characterized in that: described constant temperature treatment temperature is about 360 ℃.
8. as each described combining method of copper and aluminium alloy in the claim 1 to 7, it is characterized in that: the described constant temperature processing time is about 1 to 4 hour.
9. combining method of copper and aluminium alloy as claimed in claim 8 is characterized in that: the described constant temperature processing time is about 2 to 3 hours.
10. combining method of copper and aluminium alloy as claimed in claim 9 is characterized in that: the described constant temperature processing time is about 3 hours.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN200410077431.4A CN1785571A (en) | 2004-12-09 | 2004-12-09 | Combining method of copper and aluminium alloy |
| US11/163,425 US20060124205A1 (en) | 2004-12-09 | 2005-10-18 | Method for combining components made of different materials |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN200410077431.4A CN1785571A (en) | 2004-12-09 | 2004-12-09 | Combining method of copper and aluminium alloy |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN1785571A true CN1785571A (en) | 2006-06-14 |
Family
ID=36582402
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN200410077431.4A Pending CN1785571A (en) | 2004-12-09 | 2004-12-09 | Combining method of copper and aluminium alloy |
Country Status (2)
| Country | Link |
|---|---|
| US (1) | US20060124205A1 (en) |
| CN (1) | CN1785571A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106077937A (en) * | 2016-06-24 | 2016-11-09 | 西安理工大学 | A kind of preparation method of al cu bimetal composite |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7917030B2 (en) * | 2007-12-03 | 2011-03-29 | Buabbud George | Fiber optic communication system with automatic line shutdown/power reduction |
| GB2484875A (en) * | 2009-08-28 | 2012-04-25 | Shell Int Research | System and method for anchoring an explandable tubular to a borehole wall |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2911710A (en) * | 1956-06-04 | 1959-11-10 | Crane Co | Composite body of magnesium and steel, and method of making same |
| US3256598A (en) * | 1963-07-25 | 1966-06-21 | Martin Marietta Corp | Diffusion bonding |
| US3680197A (en) * | 1969-11-05 | 1972-08-01 | United Aircraft Corp | Diffusion bonding method |
| US4252263A (en) * | 1980-04-11 | 1981-02-24 | General Electric Company | Method and apparatus for thermo-compression diffusion bonding |
| US4444352A (en) * | 1981-09-17 | 1984-04-24 | General Electric Company | Method of thermo-compression diffusion bonding together metal surfaces |
| US6427904B1 (en) * | 1999-01-29 | 2002-08-06 | Clad Metals Llc | Bonding of dissimilar metals |
| US6886736B1 (en) * | 2003-10-07 | 2005-05-03 | Veniamin V. Gubarev | Method of diffusion welding of different metals in air |
| US20060273450A1 (en) * | 2005-06-02 | 2006-12-07 | Intel Corporation | Solid-diffusion, die-to-heat spreader bonding methods, articles achieved thereby, and apparatus used therefor |
-
2004
- 2004-12-09 CN CN200410077431.4A patent/CN1785571A/en active Pending
-
2005
- 2005-10-18 US US11/163,425 patent/US20060124205A1/en not_active Abandoned
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106077937A (en) * | 2016-06-24 | 2016-11-09 | 西安理工大学 | A kind of preparation method of al cu bimetal composite |
| CN106077937B (en) * | 2016-06-24 | 2018-08-03 | 西安理工大学 | A kind of preparation method of aluminum-copper duplex metal composite material |
Also Published As
| Publication number | Publication date |
|---|---|
| US20060124205A1 (en) | 2006-06-15 |
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