JP2990027B2 - Method of manufacturing aluminum alloy brazing sheet for heat exchanger - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an aluminum alloy brazing sheet for a heat exchanger used as a component of a heat exchanger for an automobile or the like.
Aluminum alloy brazing for heat exchangers with high strength after brazing, excellent external and internal corrosion resistance after heat exchanger members, and excellent heat exchange performance as heat exchangers, made into tubes by ERW etc. The present invention relates to a sheet manufacturing method.

[0002]

2. Description of the Related Art A heat exchanger such as a radiator is shown in FIG.
As shown in FIG. 2, thin fins 2 formed into a corrugated shape are integrally formed between a plurality of flat tubes 1, and both ends of the flat tubes 1 are respectively opened to spaces formed by a header 3 and a tank 4. The high-temperature refrigerant is sent from the space on one tank side through the flat tube 1 to the space on the other tank 4 side, and the refrigerant cooled by the heat exchange between the tube 1 and the fin 2 is circulated again. is there.

A tube material and a header material of such a heat exchanger are made of, for example, JIS-3003 alloy as a core material, and JIS-7072 is used as a lining material on the inner side of the core material, that is, on the side which is always in contact with the refrigerant.
A brazing sheet clad with an alloy and a brazing material such as JIS-4045 is usually used outside the core material, and is integrally assembled together with other members such as corrugated fins by brazing. As the brazing method, a vacuum brazing method, a flux brazing method, a Nocolok brazing method using a non-corrosive flux, or the like is used, and the brazing is performed by heating to a temperature around 600 ° C.

[0004]

However, in recent years, heat exchangers have been reduced in size and weight, and therefore, it has been desired to reduce the thickness of the material. However, when the thickness is reduced in the category of the related art, there are the following problems. First, a high-strength alloy capable of sufficiently reducing the thickness of the refrigerant passage constituting member (tube material brazing sheet) has not been obtained. Next, when the thin high-strength material is subjected to ERW processing (method for processing and welding the brazing sheet to the coolant passage constituting member), the formability before welding is inferior, the core material after ERW welding has micro cracks, and the sacrificial material Is peeled off from the core material, a step occurs in the welded portion, and the like. In particular, the defect problems (1) and (2) were very serious because, when the electric resistance welded pipe was used as a radiator for an automobile, corrosion of a welded portion could be accelerated.

[0005] Defects generated by the above-described electric resistance welding depend on molding conditions before welding, welding conditions, alloy compositions of tube materials, and the like. In particular, the core material contains a large amount of Si or Cu in order to improve the strength, and a large amount of Mg or the like is often added to the sacrificial material. In order to ensure high strength, it is unavoidable that the amount of these alloying elements increases, and all the properties such as strength, brazing properties, corrosion resistance, electric resistance workability, weldability, etc. are satisfied by the conventional technology. It was impossible.

[0006]

In view of such circumstances, the present inventors have conducted intensive studies on the causes of the occurrence of defects in welds and found that the Cu-based compound distributed in the core material or the core material was sacrificed. It was found that Mg-Si based fine compounds precipitated along the interface of the material had an effect. That is, when the amount of Cu contained for increasing the strength is increased, stress concentrates around a large number of Cu-based compounds distributed in the core material during electric resistance welding, so that micro-cracks tend to occur. Also, Si in the core material and Mg in the sacrificial material react with each other, and a large amount of Mg-Si-based fine compounds precipitate along the interface between the sacrificial material and the core material, and the vicinity thereof is easier to melt than the matrix. As a result, the sacrificial material in the vicinity of the welded portion is easily peeled off from the interface with the core material. Intermediate annealing is performed under the same conditions as before,
For example, when the heat treatment is performed at about 300 to 400 ° C. for about 2 to 3 hours, a fine Mg-Si compound is precipitated along the interface between the sacrificial material and the core material, which actually causes defects during electric resistance welding. Also, if cooling after intermediate annealing is performed under the same slow conditions of 10 to 100 ° C / hr as before, Cu-based compounds are formed in the core material during the cooling process, and micro cracks occur in the core material during ERW. , Etc. Based on such knowledge, the alloy composition of the core material and the sacrificial material of the three-layer brazing sheet was searched, and the production conditions were examined, including the electric resistance workability, strength, brazing property, and corrosion resistance. Thus, a method of manufacturing an aluminum alloy brazing sheet for a heat exchanger having excellent properties such as the above has been completed.

That is, the invention of claim 1 is characterized in that Si 0.2 to 1.5 wt.
%, Cu0.05-1.5wt%, Mn0.05-2.0wt%, brazing material made of aluminum alloy is clad on one side of aluminum alloy core material consisting of aluminum and unavoidable impurities, and the other side Aluminum alloy brazing for heat exchangers with a three-layer cladding material containing 0.5 to 6.0 wt% of Zn and 0.8 to 2.5 wt% of Mg and clad with an aluminum alloy sacrificial material consisting of the balance aluminum and unavoidable impurities In the method for producing a sheet, the clad material is hot-rolled, then cold-rolled, and during the cold-rolling, at an ultimate temperature of 400 to 550 ° C. for 1 to 60 seconds, and then at 100 ° C./min. This is a method for producing an aluminum alloy brazing sheet for a heat exchanger, wherein intermediate annealing for cooling at a cooling rate is performed, and finish rolling is performed in a cold state.

[0008] The invention of claim 2 is characterized in that 0.2 to 1.5 wt% of Si, Cu
Contains 0.05 to 1.5 wt%, Mn 0.05 to 2.0 wt%, and Mg 0.03 to
0.5wt%, Cr0.03-0.3wt%, Zr0.03-0.3wt%, Ti0.03--0.
3 wt%, Ni 0.03 to 1.5 wt% containing one or more kinds, the remaining part of the aluminum alloy core material consisting of aluminum and unavoidable impurities clad brazing material made of aluminum alloy, One side Zn0.5-6.0wt%, Mg0.8
A method of manufacturing a clad material having a three-layer structure in which an aluminum alloy sacrificial material containing the remaining aluminum and unavoidable impurities is clad in an aluminum alloy brazing sheet for a heat exchanger. Cold rolling, then cold rolling, and during the cold rolling, after holding at an ultimate temperature of 400 to 550 ° C. for 1 to 60 seconds, 100 ° C.
A method for producing an aluminum alloy brazing sheet for a heat exchanger, wherein intermediate annealing for cooling at a cooling rate of not less than / min. is performed, and finish rolling is performed in a cold state.

The invention of claim 3 is characterized in that: Si 0.2 to 1.5 wt%, Cu
0.05 to 1.5 wt%, containing 0.05 to 2.0 wt% of Mn, a brazing material made of an aluminum alloy is clad on one surface of an aluminum alloy core material containing the balance of aluminum and unavoidable impurities, and Zn 6.0 wt%, Mg 0.8-2.5 wt%, Mn 0.05-1.6 wt%, In 0.002-0.3 wt%, Sn0.002
Manufactures a three-layer clad material containing an aluminum alloy sacrificial material containing at least one or more of 0.3 wt% and the balance of aluminum and unavoidable impurities into an aluminum alloy brazing sheet for a heat exchanger. In the method, the clad material is hot-rolled and then cold-rolled, and is maintained at an ultimate temperature of 400 to 550 ° C. for 1 to 60 seconds and then cooled at a cooling rate of 100 ° C./min. A method for producing an aluminum alloy brazing sheet for a heat exchanger, wherein intermediate annealing is performed and finish rolling is performed in a cold state.

The invention according to claim 4 is characterized in that Si 0.2 to 1.5 wt%, Cu
Contains 0.05 to 1.5 wt%, Mn 0.05 to 2.0 wt%, and Mg 0.03 to
0.5wt%, Cr0.03-0.3wt%, Zr0.03-0.3wt%, Ti0.03--0.
3 wt%, Ni 0.03 to 1.5 wt% containing one or more kinds, the remaining part of the aluminum alloy core material consisting of aluminum and unavoidable impurities clad brazing material made of aluminum alloy, One side Zn0.5-6.0wt%, Mg0.8
~ 2.5wt%, Mn0.05 ~ 1.6wt%, In0.002 ~ 0.
3 wt%, Sn 0.002 to 0.3 wt%, containing one or more kinds, and clad aluminum alloy sacrificial material consisting of aluminum and unavoidable impurities with a three-layer structure clad material, aluminum for heat exchanger In the method for producing an alloy brazing sheet, the clad material is hot-rolled, then cold-rolled, and in the middle of the cold-rolling, the temperature is maintained at 400 to 550 ° C. for 1 to 60 seconds and then 100 ° C./min. A method for producing an aluminum alloy brazing sheet for a heat exchanger, which comprises performing intermediate annealing for cooling at the above-described cooling rate, and further performing finish rolling in a cold state.

First, the brazing sheet manufactured according to the present invention has a three-layer structure shown in FIG. That is, the core material 5 is made of a high-strength aluminum alloy, and the brazing material 6 is clad on one surface of the core material 5 and the sacrificial material 7 is clad on the other surface. When assembling into a heat exchanger, the brazing material 6 is used on the outside and the sacrificial material 7 is used on the refrigerant passage side. In the present invention, the core material alloy contains high-strength alloying elements Si and Cu, and the amount of addition is large.
That is, it is an aluminum alloy core material containing 0.2 to 1.5 wt% of Si and 0.05 to 1.5 wt% of Cu.

The role of each additive element in the core alloy will be described below. Si contributes to strength improvement. If Si is less than 0.2 wt%,
Since the effect is not sufficient and the content does not deteriorate the electric resistance workability, there is no need to adopt the production conditions of the present invention. If the amount of Si exceeds 1.5 wt%, the core material may be melted when the soldering heat is applied, and when corrosion proceeds beyond the sacrificial material layer, there is a problem that the corrosion resistance is reduced. Therefore, Si is 0.2w
The content is set to not less than t% and not more than 1.5% by weight.

Mn forms an intermetallic compound and is distributed in the alloy to improve the strength without deteriorating the corrosion resistance.
If the amount is less than 0.05 wt%, the effect is not sufficient,
If it exceeds t%, the moldability will be reduced and the brazing sheet will be broken during processing such as assembly. Therefore, Mn is 0.05wt%
The content is set to 2.0 wt% or less, and particularly, stable characteristics are exhibited around 0.5 to 1.5 wt%, and the characteristics are dramatically improved around 0.8 to 1.2 wt%.

[0014] Cu is present in the alloy in a solid solution state and contributes to the improvement of strength. If Cu is less than 0.05 wt%, the effect of improving strength is not sufficient. Considering corrosion resistance, the upper limit of the amount of Cu is preferably 1.5 wt%. Therefore, although Cu is set to 0.05 wt% or more and 1.5 wt% or less, particularly, 0.3 to 1.0 wt% shows stable characteristics.

Mg exists in a solid solution state and as a fine precipitate of Mg ₂ Si in the alloy, and improves the strength. If the content is less than 0.03 wt%, the effect is not obtained. If the content exceeds 0.5 wt%, when brazing using a non-corrosive flux, the flux reacts with Mg to make brazing impossible. Therefore, Mg
Is 0.03 wt% or more and 0.5 wt% or less, especially 0.05-0.2 wt%
Shows stable characteristics.

Cr, Zr, and Ti all have the function of forming fine intermetallic compounds to improve the strength of the alloy. However, if each content is less than 0.03 wt%, the effect is not obtained, and if each content exceeds 0.3 wt%, the formability is reduced, and the brazing sheet is broken during processing such as assembly.
Therefore, Cr, Zr, and Ti are all set to 0.03 wt% or more and 0.3 wt% or less. In particular, it shows stable characteristics at 0.05 to 0.2 wt%. Ni also has the function of forming fine intermetallic compounds and improving the strength of the alloy. However, less than 0.03wt% has no effect.
If the content exceeds 1.5 wt%, the formability is reduced, and the brazing sheet is broken during processing such as assembly. Therefore, Ni is 0.03
Although the content is set to not less than wt% and not more than 1.5 wt%, stable characteristics are exhibited particularly at 0.2 to 0.8 wt%.

The components of the core alloy of the present invention have been described above.
Fe is a typical element of the inevitable impurities. Fe is 1.2w
If it is at most t%, it may be contained. Elements other than the above, such as B, added for refining the ingot structure may be contained as long as each element is 0.05 wt% or less.

Next, the brazing alloy used in the present invention will be described. For brazing material, JIS-4343 (Al-7.5wt% Si)
Alloy, JIS-4045 (Al-10wt% Si) alloy, JIS-4047 (Al-12wt% S
i) Alloy, JIS-4004 (Al-10wt% Si-1.5wt% Mg) alloy, Al-10w
t% Si-1.5 wt% Mg-0.1wt% Bi alloy and other Al-Si alloys with a small amount of element added to brazeability and corrosion resistance
Alloys can be applied. Furthermore, for the purpose of improving corrosion resistance,
Brazing materials that can ensure sufficiently good brazing properties when the brazing temperature is lowered below 600 ° C, such as Al-Si-Cu-Zn-based alloys, are also brazing alloys for brazing sheets limited by the present invention. Applicable as In particular, the range of the additive element is Al
-7 ~ 12wt% Si- 0.8 ~ 3wt% Cu- 0.05 ~ 0.4wt% Fe-1 ~ 5wt% Zn
The alloy has excellent properties.

Next, the role of each alloy element of the sacrificial material will be described. Zn imparts a sacrificial effect to the sacrificial material alloy. If the amount is less than 0.5 wt%, the effect is not sufficient, and the amount is 6.0 wt%
If it exceeds, the melting point decreases and it melts during brazing.
Therefore, the content of Zn is set to 0.5 to 6.0 wt%, but is set to 1.5 to 5.
0 wt% is desirable, and especially 2.5 to 4.5 wt% shows an excellent sacrificial effect. The addition of In and Sn also gives a sacrificial effect to the alloy. If the amount is less than 0.002 wt%, the effect is not sufficient, and
If the content exceeds wt%, the rolling workability of the alloy is reduced, and the alloy is not suitable as a sacrificial material for a brazing sheet having a three-layer structure. Therefore, while the In and Sn contents are each limited to 0.002 to 0.3 wt%, an excellent sacrificial effect is exhibited particularly at 0.02 to 0.15 wt%.

Mg enhances the strength of the sacrificial material and improves the strength of the entire brazing sheet. If the amount is less than 0.8 wt%, the effect is not sufficient, and if it exceeds 2.5 wt%, it becomes difficult to roll the clad material. Even if rolling can be performed, the melting point decreases and the material melts during brazing. Therefore, the amount of Mg is 0.8-2.5wt%
However, the balance between strength and sacrificial effect is particularly excellent at 1.0 to 2.2 wt%.

Mn also increases the strength of the sacrificial material and improves the strength of the entire brazing sheet. If the amount is less than 0.05% by weight, the effect is not sufficient, and if it exceeds 1.6% by weight, the rolling workability is reduced, and the material is not suitable as a sacrificial material used for a brazing sheet having a three-layer structure. Therefore, the amount of Mn is limited to 0.05 to 1.6% by weight, and particularly in the composition range of 0.5 to 1.2% by weight, the balance between strength and rolling workability is preferable.

The alloy elements of the sacrificial material of the present invention are as described above. Next, unavoidable impurities will be described. Si is 0.5w
There is no problem if it is at most t%, but particularly preferably at most 0.1 wt%. There is no problem if Fe is 0.8 wt% or less, especially 0.1 wt%
The following is desirable. Elements such as Cr, Zr, and Ti, which have a strength improving effect, may be contained as impurity elements as long as each is 0.05 wt% or less. The thickness or coverage of the brazing material and the sacrificial material of the brazing sheet having a three-layer structure is determined by the thickness of the entire brazing sheet and the like, but is usually about 30 μm.

Next, the manufacturing conditions in the present invention will be described. In the present invention, the intermediate annealing placed in the middle of the cold rolling is held at an ultimate temperature of 400 to 550 ° C. for 1 to 60 seconds, and after the holding,
Cool at a cooling rate of 0 ° C / min. The reason for limiting the intermediate annealing temperature to 400 to 550 ° C is that the intermediate annealing temperature is
If the temperature is lower than 00 ° C., the solution treatment is not completed, and the Mg-Si
This is because the system compound precipitates along the interface between the sacrificial material and the core material to cause defects in the welded portion, and if the temperature exceeds 550 ° C, the brazing material may be melted. The reason why the holding time is limited to 1 to 60 seconds is that the solution treatment is not complete in less than 1 second, and the sacrificial material and the core material each increase in the amount of added element diffusion after 60 seconds,
This is because brazing properties and corrosion resistance may be significantly reduced. The reason why the cooling rate was limited to 100 ℃ / min.
If the cooling rate is less than 100 ° C / min.
Even if the temperature is kept at 1 ° C. for 1 to 60 seconds, the Al-Cu-based compound may precipitate during the cooling, and a defect may be generated in the welded portion during the electric resistance welding. In particular, if cooling is performed at a rate of 500 ° C./min. Or more, the brazing sheet can be subjected to ERW processing with better weldability.

The heating rate in the intermediate annealing is not particularly limited, but by performing the heating within the same condition range as the cooling rate limited in the present invention, the recrystallized grains of the core material can be made fine and uniform. It has been obtained as a new finding that stress concentration that causes microcracking of the core material at the time is reduced. Further, the higher the heating rate, the better the productivity is, which is preferable. Especially,
It is effective when performing the intermediate annealing online. If the heating rate is too slow, diffusion can be accelerated and other properties can be adversely affected. Judging from the viewpoints of temperature control, furnace use cost, and securing of overall material properties, it is desirable that the heating rate be about the same as the cooling rate. Other production conditions are not particularly limited, but the starting temperature of hot rolling is set to 420 to
It is desirable that the temperature range is 520 ° C. and the final cold rolling reduction in the cold rolling is 20 to 50%. Further, in consideration of formability, a stabilization treatment may be performed at a temperature of 200 to 300 ° C. after the final cold rolling.

The brazing sheet having a three-layer structure manufactured according to the present invention can be formed into a tube by an electric sewing process or the like.
It is brazed as it is as a header material and used as a heat exchanger. The brazing conditions may be almost the same as the conventional one. That is, a flux brazing method, a Nocolok brazing method using a non-corrosive flux, or the like may be used, and there is no particular limitation. Assembling before brazing,
Cleaning, flux application, etc. may be performed as usual. In this case, for example, a cesium-based flux may be used. In the present invention, the step after heating is not particularly limited. As conventionally performed, steps such as aging treatment, flux removal, and painting may be performed.

[0026]

[Table 1]

[0027]

[Table 2]

[0028]

The present invention will be specifically described below with reference to examples. (Example 1) A three-layer brazing sheet having a thickness of 0.25 mm for an aluminum alloy tube having the composition shown in Table 1 was produced through the intermediate annealing conditions shown in Table 2. For comparison, a conventional method was used. The clad ratio of the brazing material of the method product of the present invention and the comparative example was 10%, and the cladding ratio of the sacrificial material was 20%. However, the sacrificial material clad rate of the current material was set to 10%. In the sacrificial material, Fe and Si as impurity elements are each 0.01 to 0.2 watts.
It is included in the range of t%. JIS-4045 alloy or brazing material
Al-Si-Cu-Zn alloy was used. These coiled brazing sheet plates were slit to 56.0 mm strip according to the size of the ERW pipe. This strip was processed into an electric resistance welded pipe having a width of 27.0 mm and a thickness of 1.9 mm for a liquid passage pipe using an electric resistance welded pipe manufacturing apparatus. Table 3 shows the evaluation results of the electric resistance workability of each strip material. Evaluation items include leakage, pressure resistance performance by internal hydrostatic pressure test,
The core micro-cracking, sacrificial material peeling, step, and dimensional accuracy at the ERW weld were examined. The results are shown in Table 3.

[0029]

[Table 3]

As is apparent from Table 3, the method products of the present invention (Nos. 1 to 11 and 20 to 22) have good quality of the ERW welds, and no leaks are found in the ERW pipes. Also, the pressure resistance was excellent and no breakage from the weld occurred. In contrast, Nos. 17 to 19 of Comparative Examples had alloy compositions out of the limited range of the present invention, and Nos. 12 to 15 had manufacturing conditions out of the conditions of the present invention. In both No. 16 and No. 18, both the alloy composition and the manufacturing conditions were out of order, so that the ERW workability deteriorated in both cases.

Example 2 The same sample (three-layer brazing sheet having a thickness of 0.25 mm) used in Example 1 was used.
After heating and holding in a nitrogen gas at 595 ° C. × 3.5 min., The tensile strength, corrosion resistance, and brazing property were tested, and the weldability (brazing property) was investigated. Corrosion resistance is immersed in tap water to which 10 ppm of Cu ²⁺ ion is added,
A cyclic corrosion test at 80 ° C. for 8 hours and at room temperature for 16 hours was performed for 5 months, and the depth of pits generated on the surface of the sacrificial material was determined by a depth of focus method using an optical microscope. The brazing property was evaluated by a T-shaped fluidity test, and the appearance was visually evaluated. The results are shown in Table 4. In addition, the rolling property when rolling to a 0.25 mm plate material is also shown. The rollability was determined by observing the occurrence of edge cracks, rough skin, plate breakage and the like during cold rolling.

[0032]

[Table 4]

As is apparent from Table 4, all of the products of the present invention (Nos. 1 to 11, 20 to 22) exhibited good characteristics. In addition, in the weldability test, the characteristics of No. 12 to No. 15 of the comparative example products were not particularly deteriorated. However, in No. 16, since the amount of Mg in the sacrificial material was large, a large amount of the Mg-Si-based compound was precipitated at the interface between the core material and the sacrificial material, and the two were separated, making it impossible to roll. No.1
In Nos. 7 and 18, the sacrificial material contained no Mg, and the amount of Zn was too small, and the corrosion resistance was reduced. No. 19 was poor in rollability and partially melted due to excessive amounts of Si and Cu in the core material.

[0034]

As described above, according to the method of the present invention, aluminum which is excellent in electric resistance workability, high in strength and excellent in corrosion resistance, does not melt at the time of brazing, and can reduce the size and weight of the heat exchanger. An alloy brazing sheet is obtained, which has an industrially remarkable effect.

[Brief description of the drawings]

FIG. 1 is a partially sectional perspective view showing a radiator.

FIG. 2 is a sectional view showing the structure of the brazing sheet of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Flat tube 2 Fin 3 Header 4 Tank 5 Core material 6 Brazing material 7 Sacrificial material

────────────────────────────────────────────────── ─── front page continued (51) Int.Cl. ⁶ identifications FI F28F 21/08 F28F 21/08 a // C22F 1/00 627 C22F 1/00 627 640 640A 651 651A 683 683 685 685Z 686 686Z 691 691B 691C 692 692A (58) Fields investigated (Int. Cl. ⁶ , DB name) C22F 1/04 B23K 20/04 B23K 35/22 310 B23K 35/40 340 C22C 21/00 F28F 21/08

Claims (4)

(57) [Claims] (1) Si 0.2 to 1.5 wt%, Cu 0.05 to 1.5 wt%, Mn0.
One part of an aluminum alloy core material containing 0.05 to 2.0 wt% and the balance of aluminum and unavoidable impurities is clad with a brazing material made of an aluminum alloy, and Zn 0.5
A method of manufacturing a three-layer clad material containing aluminum alloy sacrificial material containing up to 6.0 wt%, Mg 0.8 to 2.5 wt% and the balance of aluminum and inevitable impurities into an aluminum alloy brazing sheet for a heat exchanger. In, the clad material is hot-rolled, then cold-rolled,
During the cold rolling, the temperature reaches 400 to 550 ° C and 1 to 60.
A method for producing an aluminum alloy brazing sheet for a heat exchanger, comprising: performing intermediate annealing for cooling at a cooling rate of 100 ° C./min. Or more after holding for 2 seconds, and finish rolling in a cold state. (2) Si 0.2 to 1.5 wt%, Cu 0.05 to 1.5 wt%, Mn0.
Contains 0.05 to 2.0 wt%, Mg 0.03 to 0.5 wt%, Cr 0.03 to 0.
3wt%, Zr0.03-0.3wt%, Ti0.03-0.3wt%, Ni0.03-1.5w
t%, one or two or more of them, the balance of aluminum alloy core material consisting of aluminum and unavoidable impurities is clad on one side with an aluminum alloy brazing material, and on the other side Zn 0.5-6.0 wt% , A method of manufacturing a three-layered clad material containing 0.8 to 2.5 wt% of Mg and clad with an aluminum alloy sacrificial material comprising the balance of aluminum and unavoidable impurities into an aluminum alloy brazing sheet for a heat exchanger, Hot rolling, then cold rolling, during the cold rolling, the ultimate temperature 400-55
A method for producing an aluminum alloy brazing sheet for a heat exchanger, comprising: holding at 0 ° C. for 1 to 60 seconds; cooling at a cooling rate of 100 ° C./min. Or more; (3) Si 0.2 to 1.5 wt%, Cu 0.05 to 1.5 wt%, Mn0.
One part of an aluminum alloy core material containing 0.05 to 2.0 wt% and the balance of aluminum and unavoidable impurities is clad with a brazing material made of an aluminum alloy, and Zn 0.5
~ 6.0wt%, Mg0.8 ~ 2.5wt%, Mn0.05 ~ 1.6wt
%, In 0.002 ~ 0.3wt%, Sn 0.002 ~ 0.3wt% containing one or more kinds, the cladding material of the three-layer structure clad aluminum alloy sacrificial material consisting of the remaining aluminum and unavoidable impurities, In the method for producing an aluminum alloy brazing sheet for a heat exchanger, the clad material is hot-rolled, then cold-rolled, and held at an ultimate temperature of 400 to 550 ° C. for 1 to 60 seconds during the cold rolling. ° C
A method for producing an aluminum alloy brazing sheet for a heat exchanger, which comprises performing intermediate annealing for cooling at a cooling rate of not less than / min. (4) Si 0.2 to 1.5 wt%, Cu 0.05 to 1.5 wt%, Mn0.
Contains 0.05 to 2.0 wt%, Mg 0.03 to 0.5 wt%, Cr 0.03 to 0.
3wt%, Zr0.03-0.3wt%, Ti0.03-0.3wt%, Ni0.03-1.5w
One or two or more of the t%, aluminum alloy core material consisting of the remaining aluminum and unavoidable impurities clad brazing material made of aluminum alloy on one side, Zn 0.5-6.0 wt% on the other side, 0.8-2.5wt% Mg
Mn0.05-1.6wt%, In 0.002-0.3wt%, Sn 0.002-0.3wt%
A method of manufacturing a clad material having a three-layer structure in which one or two or more of them are contained and a clad aluminum alloy sacrificial material comprising the balance of aluminum and unavoidable impurities is used as an aluminum alloy brazing sheet for a heat exchanger, The clad material is hot rolled, then cold rolled,
During the cold rolling, the temperature reaches 400 to 550 ° C and 1 to 60.
A method for producing an aluminum alloy brazing sheet for a heat exchanger, comprising: performing intermediate annealing for cooling at a cooling rate of 100 ° C./min. Or more after holding for 2 seconds, and finish rolling in a cold state.