JPS6033346A - Preparation of fin material or brazing sheet for heat exchanger - Google Patents

Abstract

PURPOSE:To prepare a fin material or a brazing sheet for a heat exchanger without generating high temp. deformation during brazing, by applying three times of cold rolling processings containing two times of annealings under a specific condition to a combined material comprising a core material and a skin material both of which are made of Al-alloys having specific compositions. CONSTITUTION:An Al-alloy containing 0.5-2.0% Mn, 0.1-1.0% Si and, if necessary, 0.01-0.2% Zr or an Al-alloy further contaning one or more of 0.2-2.0% Zn, 0.002-0.1% Sn and 0.002-0.1% In is used as a core material and an Al-Si alloy or an Al-Si-Mg alloy is used as a skin material to prepare a combined plate. This combined plate is subjected to hot rolling, cold rolling and intermediate annealing at a temp. from 200 deg.C to a perfect re-crystallizing temp. In the next step, the formed plate is cold rolled under a draft of 5-65% and, thereafter, again annealed at a temp. from a recrystallizing stemp. to 450 deg.C and succeedingly subjected to third cold rolling under a draft of 25-65% to prepare a fin material or a brazing sheet for a heat exchanger.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to fin materials used in various heat exchangers such as bonders/sleeves and evaporators of automobile coogies, and plating sheets for heat exchanger fin materials.

As is well known, in heat exchangers such as condensers and evaporators for automobile coolers, aluminum alloy fin material is usually used in the tubes or pipes through which the temperature medium (working fluid) flows. However, recently, as a fin material in this case, a plating sheet, that is, a plating sheet in which a skin material made of an aluminum alloy brazing material is preliminarily applied to both or one side of an aluminum alloy core material is often used. Conventional plating sheets of this type have core materials such as JIS A 3003 alloy and JIS A 6951 alloy, Al1-
Mn-based alloy or Al-Mg-Si-based alloy is used, and the skin material is JIS B A 4004 alloy or JIS B A
Usually, a kl-Si-Mg-based or AA-Si-based braze alloy is used, such as 4343 alloy.

By the way, conventional plating sheets for heat exchangers are extremely thin, usually 0.1.6ffll11, and
The problem is that during brazing, that is, when brazing heat exchanger tubes or pipes, the fins are exposed to high temperatures of around 600°C, which can cause distortion and bending of the fins due to high temperature deformation, which can reduce product value. There is. In particular, recently, in order to reduce the weight and cost of heat exchangers, there has been a demand for thinner fin plates than currently available, which has made the problem of high-temperature deformation as described above even more important. are doing.

As a measure to deal with cedar (high temperature during brazing as described above), the following two types of measures have been proposed or put into practical use from the perspective of improving the quality of the core material itself.゛Firstly, there is a way to adjust the alloy composition of the core material. For example, adding Zr or Cr to an Al-Mn alloy.
A method of adding trace amounts of components such as the following is known. Also the second
There are measures to adjust the manufacturing process of the core material, for example, A.
Measures have been attempted to define intermediate annealing conditions during cold rolling of a-Mn-Zr alloys. However, although these measures are effective to some extent against high-temperature deformation in conventional general plating sheets, the reality is that they cannot sufficiently meet the recent demands for thinner walls. , the heat exchanger is placed on a lifting platform exposed to a severe corrosive environment.
There is a risk of pitting corrosion occurring from the air side of the tube material that makes up the working fluid (temperature medium) 7If circuit and leakage of the working fluid.In order to avoid this, the core material of the plating sheet of the fin material It has been observed in the past that Sn, Zn, etc. are added to give the fin material a sacrificial anode effect to prevent corrosion of the fin material. However, in this way Sn.

If an element such as Zn is added to the plating sheet core material to provide a sacrificial anode effect, the corrosion resistance of the heat exchanger is improved, but there is a problem in that the high temperature deformation resistance is significantly reduced.

In addition, as a fin material for the heat exchanger of automobile coolers,
Instead of using a glazing sheet as described above, it is also possible to apply brazing material to the surface of the chive material that constitutes the working fluid passage, and then braze the fin material of a single plate (not a laminated board) to the chive material. It is being done. Even in such a single-plate fin material, the same problem of high-temperature deformation as described above cannot be avoided due to the high temperatures exposed during brazing during the manufacture of a heat exchanger. Also, in the case of a single fin material, Sn
As mentioned above, when elements such as , Zn, etc. are added to give a sacrificial anode effect, the high temperature deformation resistance is significantly deteriorated.

This invention was made in view of the above circumstances, and it has been made to significantly improve the high temperature deformation resistance of a plating sheet for a heat exchanger or a fin material of a veneer for a heat exchanger compared to the conventional one, and to improve the resistance to deformation during brazing heating. We provide plating sheets and fin materials that are resistant to distortion and bending, and also provide sufficient high-temperature deformation resistance even when Sn and Zn are added to increase corrosion resistance due to the sacrificial anode effect. The purpose is to provide sheets and fin materials.

In order to achieve the above-mentioned object, the present inventors have carried out extensive experiments and studies, and as a result, in the manufacturing process of plating sheets or veneer-like fin materials, the number of intermediate annealing in the cold rolling process after hot rolling has been reduced. The temperature conditions for the first intermediate annealing and the second intermediate annealing are set to different temperatures, the first being lower than the recrystallization temperature and the second being higher than the recrystallization temperature. At the same time, the cold rolling during these intermediate annealing and the final cold rolling
It was discovered that the above-mentioned object can be achieved by setting the rolling ratio (rolling ratio) within a certain appropriate range, and the present invention was completed.

Specifically, the first invention relates to a method for manufacturing a veneer-like fin material, in which Mn is 0.5 to 2.0%, 5iO01
~1.0% and optionally Zr0.01~0
, 2, and the remainder being Al and unavoidable impurities, in a method for producing a fin material for a heat exchanger by hot rolling and cold rolling, the hot rolled upper plate is first successively rolled. After this, the cold-rolled sheet is subjected to a first intermediate annealing at a temperature of 200°C or higher and lower than the complete recrystallization temperature, then subjected to a second successive rolling at a rolling reduction of 5 to 65 inches, and then re-annealed. It is characterized by performing a second intermediate annealing (final intermediate annealing) at a temperature above the crystallization temperature and below 450°C, followed by a third successive rolling (final cold rolling) at a reduction rate of 25 to 65%. It is something to do.

Further, the second invention relates to a method for manufacturing a veneer-like fin material similar to the first invention, and contains 0.5 to 2.0% of Mn and 0.1 to 1.0% of Si. In order to have a sacrificial anode effect, ZnO12~2.0%, 5n0002~
Zr0.0.
In manufacturing a heat exchanger fin strip by hot rolling and cold rolling an alloy containing 1 to 0.2 H and the balance consisting of A/ and unavoidable impurities, the same steps as in the first invention are taken. It is characterized by this.

Furthermore, the third invention relates to a method for manufacturing a plating sheet for a heat exchanger fin made of laminated plates, in which the same alloy as the alloy targeted in the first invention is used as the core feather, and an Al-Si alloy is used. Alternatively, in a method of manufacturing a plating sheet for a heat exchanger by hot rolling and cold rolling a laminated sheet using Ae-Si-Mg alloy as a skin material, the first This method is characterized by using the same process as the invention (however, the rolling F ratio of the second rolling is 25 to 65%).

Similarly to the third invention, the fourth invention relates to a method for producing a glazing sheet for heat exchanger fins, which uses the same alloy as the core material as the alloy targeted in the second invention, and has an Al- Si alloy or /kl! -Si
- In a method for producing a plating sheet for a heat exchanger by hot rolling and cold rolling a laminated sheet using Mg alloy as a skin material, the same steps as in the third invention are performed for the hot rolled sheet of the laminated sheet. It is characterized by taking the following.

The manufacturing method of the present invention will be explained in detail below.

First, the reason for limiting the composition of the alloy used in the core material of the glazing sheet or the veneer-like fin material in this invention will be explained.

Mn, Si and Zr contained as necessary are
Fine compounds such as Al-Mn-Si compounds or A11-Zr compounds are dispersed and precipitated in the Al matrix by intermediate annealing between the cold rolling processes, especially the first intermediate annealing, and are recrystallized during brazing heating. It plays a role in improving high temperature deformation resistance by coarsening the grains.

Here, if the Mn content is less than 0.5 inch, the above-mentioned effects cannot be obtained, and the strength at room temperature is insufficient, resulting in deterioration of fin formability. On the other hand, if the Mn content exceeds 2.0, is it coarse AA? -Mn-based compounds are generated and the desired effect cannot be obtained. Therefore, Mn ti & in the plating sheet core material or veneer fin material is 0
．． It was limited to 5-20%.

When the Si content is less than 0.1%, fine Al-M
The amount of n -Si-based compounds produced is too small to achieve the desired effect, while if the amount exceeds 10, AA -Mn -S i
The system compound becomes coarse and the desired effect cannot be obtained. Therefore, the Si content in the plating sheet core material or veneer-like fin was limited to 0.1 to 1.0%.

In this invention, Z is an element that is optionally added to the plating sheet core material or the alloy of the veneer-like fin, but if its content is less than 0.01%, the above-mentioned effect will not be achieved. However, since it is still beyond the 02 ratio and no further improvement in the effect can be expected, and on the contrary, the workability is low, the Zr amount when adding Zr (is 0.01 to 0.2 ratio). range.

S'n, Zn, and In all make the potential of the glazing sheet or fin material less noble with respect to the cheap material that makes up the fluid passage, thereby providing a sacrificial anode effect and having the effect of preventing corrosion of the tube. .

However, ZnO, 2% not 4::'4, 'SnO,0
Less than 0.02%, In(1,002%) are not sufficiently effective; on the other hand, Zn2.0%, Sn 0.1
%, In exceeds 0.1%, the high temperature deformation resistance and rolling workability deteriorate, so in the second and fourth inventions, Z
n is in the range of 02 to 2.0, Sn is in the range of 0.002 to 0.1
% range, In was limited to a range of 0.002 to 0.1q6. Note that Zn and Sn.

Only one type of In may be added, or two or more types may be added.

On the other hand, the alloy used for the skin material of the plating sheet may be an A7-Si alloy or an A,g-Si-Mg alloy known as an aluminum alloy brazing material. When brazing is performed by heating after applying flux, use AA! When brazing is performed in vacuum using a -Si alloy, an Al-St-Mg alloy is usually used. Furthermore, AA! - In the case of a Si alloy, it is desirable that the SL content is approximately 6 to 12%, and the A7-S
In the case of i-Mg alloy, Si 6-12%, Mg 0.5-12%
It is desirable to set it to about 2%.

Next, the manufacturing process of this invention will be explained.

When manufacturing a plating sheet, first, a core material and a skin material are hot-rolled together, and then the two are bonded together by thermocompression. That is, for example, an ingot of the skin material is rolled in advance to a predetermined thickness using a roll, and this is superimposed on one or both sides of the core ingot, and hot-rolled in this state.

On the other hand, when producing a single-plate fin material, the ingot is individually hot rolled.

The hot-rolled plate hot-rolled as described above is first subjected to first successive rolling. In this first successive rolling step, the hot rolled structure is changed to a cold rolled structure, and precipitation of fine #Ifl compounds in the subsequent first intermediate annealing step is promoted.

Note that the rolling reduction rate in this first successive rolling step is not particularly specified, but may be determined to be an appropriate rolling reduction ratio in consideration of the thickness of the final product and the rolling reduction ratio in the second and third successive rolling steps.

For the 7'C cold plate after the first rolling is completed, 20
The first intermediate annealing, that is, the first intermediate annealing, is performed at a temperature range of 0° C. or higher and lower than the complete recrystallization temperature.

By this first intermediate annealing, a compound phase, such as an Al-Mn-Si compound or an A7-Zr compound, is finely dispersed and precipitated in the Al matrix. Here, the annealing temperature is 20
If the temperature is less than 0°C, the amount of fine compounds precipitated is not sufficient, while if the temperature is higher than the complete recrystallization temperature, the precipitated compounds become coarse, which is not preferable.

Next, the second cold rolling is performed at 2 in the case of plating sheets.
At a reduction rate of 5 to 65 inches, if the fin material is still veneer, 5
Apply at a rolling reduction of ~65 inches. Recrystallized grains are stably generated in the second intermediate annealing that follows this second cold rolling. If the rolling reduction is less than 5 inches, stable coarse recrystallization cannot be obtained in the subsequent second intermediate rolling process, and especially in the case of plating sheets, if the rolling reduction is less than 25 inches, the crystal grains of the skin material will become coarse. This is undesirable because the fluidity of the wax during brazing decreases. On the other hand, if the pressing ratio exceeds 65 inches, the crystal grains of the core material become fine, which is not preferable.

After the completion of the second cold rolling, final intermediate annealing, that is, second intermediate annealing, is performed at a temperature higher than the recrystallization temperature and lower than 450°C. By this second intermediate annealing, the crystal grains in the plating sheet core material or the veneer-like fin material become coarse. Here, if the annealing temperature is lower than the recrystallization temperature, coarse crystal grains cannot be obtained, which is not preferable. On the other hand, the annealing temperature is 4
If the temperature exceeds 50°C, precipitates will concentrate on the grain boundaries of the core material, resulting in a decrease in high temperature deformation resistance, as well as severe oxidation of the plate surface, resulting in low rolling properties. Note that the recrystallization in this second intermediate annealing step may be partial recrystallization, and therefore the temperature of the second intermediate annealing does not necessarily have to be higher than the complete recrystallization temperature, but rather than the partial recrystallization start temperature. Any above is fine.

After the second intermediate annealing is completed, final cold rolling, that is, third cold rolling, is performed at a reduction rate of 25 to 65 inches to form a plating sheet or fin material.

This final cold rolling provides desired mechanical properties and formability, and at the same time improves high-temperature deformation resistance.

If the reduction ratio is less than 25%, the desired mechanical properties and formability cannot be obtained, while if the reduction ratio exceeds 65%, the crystal grains of the core material become fine, which is not preferable.

As mentioned above, in the manufacturing method of the present invention, the intermediate annealing is divided into two stages: the first intermediate annealing at a temperature lower than the complete recrystallization temperature, and the second intermediate annealing at a temperature higher than the recrystallization temperature. This first intermediate annealing is carried out at a temperature lower than 200°C.
By carrying out the process at a temperature of .degree. C. or higher, the compound phase in the A7 parent phase of the shibrating sheet core material or fin material can be dispersed and precipitated in a fine and sufficient amount. In addition, the reduction ratio of the second cold rolling between the first intermediate annealing and the second intermediate annealing is regulated to 65% or less, and the reduction ratio of the final (tertiary) cold rolling is also regulated to 65% or less. By regulating this, it is possible to coarsen the crystal grains of the core material of the plating sheet or the veneer-like fin material as a final product. As mentioned above, the combination of coarse crystal grains and finely dispersed compound phases results in good high-temperature deformation resistance, which prevents settling and buckling due to high temperatures during brazing heating. is prevented.

Examples and comparative examples of each invention of the present application are described below.

Examples 1 to 7 Alloys having the compositions shown in alloy numbers 1 to 4 in Table 1 were melted, and ingots of these alloys were faced and then heated at 500°C for 5 hours.
Hot rolling was performed to obtain plate thicknesses in the order of 30. Next, these plates were cold rolled (first rolled) to a thickness of 0.38 to 0.64 mm.
After successive rolling), the recrystallization temperature of each alloy was determined by examining the softening curve. Subsequently, each plate was intermediately annealed (first intermediate annealing) at a temperature lower than the respective recrystallization temperature and 200°C or higher, and then subjected to a second cold rolling at a reduction rate of 25 to 65%. Ta. Furthermore, these plates are subjected to final intermediate annealing (secondary intermediate annealing) at a temperature of 450° C. or higher, above their respective recrystallization temperatures, and then final cold rolling at a rolling reduction rate of 25 to 65% (3rd century). Then, cold rolling) was performed to obtain a fin material with a thickness of 0.16 m+1. These manufacturing conditions are shown in Table 2. Next, using these fin materials as a piece with a width of 30 mm and a length of 14' (1 m test), identify the 1'' part in the longitudinal direction of the test piece, and place it with a horizontal protrusion of 6 Q mm. 610°CX
It was heated for 5 minutes, and the hanging height of the protruding end of the test JVA piece after heating was examined (sagging resistance test 11). The measurement results are also shown in the second garment.

Comparative Examples 1 to 6 The same alloys as used in Examples 1 to 7 (alloy numbers 1 to 4 in Table 1) were treated in the same manner as Examples 1 to 7 up to hot rolling and first cold rolling. did.

The subsequent process conditions were set outside the scope of the present invention, and the final result was 0.
A fin material with a thickness of 16 mm was obtained. The conditions for each process are shown in Table 2. In Table 2, Comparative Example 3 was subjected to intermediate annealing only once according to the conventional method. Furthermore, the same drooping resistance test as in Examples 1 to 7 was conducted on the fin materials of Comparative Examples 1 to 6.

The results are also shown in Table 2.

Table 1 2 Alloy components (unit weight) As is clear from Table 2, the fin chestnuts obtained in Examples 1 to 7 of the first invention were all obtained in Comparative Examples 1 to 6. Compared to fin materials, the amount of sagging in the sagging resistance test is much smaller, and it is therefore clear that the material has excellent high-temperature deformation resistance during brazing heating.

Examples 8 to 15 Alloys having the compositions shown in alloy numbers 1 to 4 in Table 1 were used as core materials,
Using alloys with compositions shown in alloy codes A and B in Table 3 as skin materials, each ingot was face-sided, the skin material was rolled to a predetermined thickness, and the skin materials were placed on both sides of the core material and hot-rolled. The core material and the skin material were hot-pressed by rolling, and the overall thickness was made 3.0 cm. Then, each cold rolling and each intermediate annealing were performed in the same manner as in Examples 1 to 7 to finally obtain a plating sheet with a thickness of Q, 16 km. The manufacturing process conditions for each plating sheet are
Shown in the table. In addition, the adhesive ratio of each plating sheet was 10 inches on each side. Table 4 also shows the results of a drooping resistance test similar to that described above for these plating sheets. However, the sheet to which Alloy A was crimped as a skin material was heated in the atmosphere at a flux coating diameter, and the sheet to which Alloy B was crimped was heated in a vacuum at 5 X i and F5 Torr.

Ratio I bite Examples 7 to 12 Using the core material and skin material similar to those used in Examples 8 to 15, the actual A li・
A plating sheet with a thickness of O, 16 mm, and a cladding ratio of 10 inches on each side was finally obtained using the same procedures as in Examples 8 to 15, except that the subsequent process conditions were outside the scope of the present invention. The respective process conditions are shown in Table 4, and the results of the sagging resistance test conducted in the same manner as in Examples f3'll 8 to 15 are also shown in Table 4.

In Comparative Example 11, intermediate annealing was performed only once according to the conventional method.

Table 3: Component composition of skin material (unit: tonne) As is clear from Table 4, plating sheets obtained in Examples 8 to 15 of the third invention were all based on Comparative Examples 7 to 12. It is clear that the amount of sagging is smaller than that of plating sheets, and that the sheet has excellent high-temperature deformation resistance. Still each example 8
All of the plating sheets prepared by Examples 1 to 15 had good moldability.

Examples 16 to 18 Regarding the alloys having the compositions shown in alloy numbers 5 to 7 in Table 5, the ingots were subjected to surface cutting at 500°C in the same manner as in Examples 1 to 7.
The material was heated for several hours and hot rolled to a thickness of 3.0 m. Then these plates are 0,38~Q, 54 +trm
After cold rolling (first cold rolling) to a thickness of , the recrystallization temperature of each alloy was determined by examining the softening curve. Examples 1 to 7 below
Similarly, the first intermediate annealing and the second
A 0.16wn thick fin material was obtained by successive rolling, second intermediate annealing, and third successive rolling.

Comparative Example 13 An alloy having the composition shown in Alloy No. 5 in Table 5 was subjected to hot rolling and first cold rolling in the same manner as Examples 16 to 18, and the steps after intermediate annealing were performed within the conditions of the present invention. This was carried out outside to obtain a 0.11 el thick fin material.

The process conditions of Examples 16 to 18 and Comparative Example 13 were changed to
Shown in the table. In addition, the above Examples 16 to 18 and Comparative Example 13
Table 6 also shows the results of a drooping resistance test similar to that described above for the fin materials obtained.

Table 5 2 Alloy components (unit: weight) From Table 6, give the sacrificial anode effect (Sn).

It is clear that even when Zn or In is added, the high temperature deformation resistance is excellent.

Examples 19 to 24 Alloys having the compositions shown in alloy numbers 5 to 8 in Table 5 were used as core materials,
Using the Al-Sl-Mg alloy indicated by alloy code B in Table 3 as a skin material, each ingot was face-sided, the skin material was rolled to a predetermined thickness, and the skin material was placed on both sides of the core material and heated. The core material and the skin material were crimped together by rolling. and Examples 16-1
8, the first cold rolling, the first intermediate annealing, and the second
Next cold rolling, second intermediate annealing, and third cold rolling were performed in that order, and finally a plating sheet with a total thickness Q of 15 m and a cladding ratio of 10% on each side was obtained. The conditions for each manufacturing process are shown in Table 7.

Comparative Examples 14-18 Using the same core material and skin material as used in Examples 19-24,
The hot rolling and the first cold rolling were the same as in Examples 14 to 18, and the subsequent process conditions were outside the scope of the present invention, and the final plate was made with a total thickness of 0.10 nnn and a cladding ratio of 10 inches on each side. I got a zing sheet. Each process condition is shown in Table 7. In Table 7, Comparative Example 18 was subjected to intermediate annealing once according to the conventional method.

Table 7 also shows the results of a sagging resistance test performed on the plating sheets obtained in Examples 19 to 24 and Comparative Examples 14 to 18 described above.

Note that the test conditions are the same as in Examples 1 to 7.

As is clear from Table 7, the plating sheets obtained in Examples 19 to 24 have significantly superior high temperature deformation resistance compared to the plating sheets obtained in Ratio Examples 14 to 18. It is clear that it has.

Furthermore, the corrosion resistance of the plating sheets obtained in Examples 19 to 24 due to the sacrificial anode effect was investigated as follows. That is, as shown in Fig. 1, the praising sheet 1 has a fin height of 20 holes, a width of 2 Qmm, and a pitch of 1.
Processed into a corrugate shape with a diameter of 0.2 mm, both sides of the corrugate are JIS 1.2 T nm thick, 20 scale wide, and 150 w long.
A 610°C x 5 in a vacuum of 5 x 1 O-5 Torr between aluminum alloy plates 2 and 3 made of 3003 alloy
A test piece was prepared by heating and brazing for a minute. And the outside of aluminum alloy plates 2 and 3 in the test piece +
i2A.

3A with paint 4 to prevent corrosion of the inner surfaces (corrugated fin 1 side) 2B and 3B of the plates 2 and 3).
Cath test based on JISH8681 (1 month exposure period)
Investigated by. As a result, the depth of pitting corrosion in the test specimens using Brazing Sea 1 obtained in each Example was extremely small, Q, 2 mm or less, and it was confirmed that the test specimens had sufficient sacrificial anode effects. For comparison, the first
Example 1 An alloy having the composition shown in alloy number 1 in the table was used as the core material.
When a corrosion resistance test similar to that described above was conducted using a glazing sheet manufactured under the same conditions as No. 9, pitting corrosion occurred for one hour or more in this case.

As is clear from the above explanation, according to the method of this invention,
It is possible to obtain a glazing sheet or fin material that has excellent high-temperature deformation resistance. Therefore, if the glazing sheet or fin material obtained by the method of this invention is used in a heat exchanger, it will not buckle or deform during brazing. can be effectively prevented from occurring, and therefore heat exchangers can be manufactured with a high yield. In particular, Sn and Zn
, even when In is added to give a sacrificial anode effect,
The glazing sheet or fin material obtained by the method of this invention has extremely high resistance to high temperature deformation, and therefore has the remarkable effect of producing heat exchangers with excellent corrosion resistance at a high yield. can get.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing the shape of the test piece used in the corrosion resistance test. Applicant Sky Aluminum Co., Ltd.

Claims (4)

[Claims] (1) Contains Mn 0.5 to 2.0% (weight ratio, the same applies hereinafter), SfO, 1 to 1%, and optionally Zr.
Contains o, oi ~ 0.2chi, and the remainder is AI! In the method of manufacturing a fin material for a heat exchanger by hot rolling and cold rolling an alloy containing unavoidable impurities, the hot-rolled plate is first cold-rolled, and then the cold-rolled plate is heated at 200°C. A first intermediate annealing is performed at a temperature above and below the complete recrystallization temperature, followed by a second successive rolling at a reduction rate of 5 to 65%, and then at a temperature above the recrystallization temperature and below 450°C. A method for manufacturing a fin material for a heat exchanger, comprising performing a second intermediate annealing, followed by a third successive rolling at a rolling reduction ratio of 25% to 65%. (2) Mn 0.5-2.0%, Si 0.1-1.
0%, and Zn 0.2-2.0%, Sn 0
．． Contains at least one type selected from 0.002~0.1% and In0.002~0.1%, and further contains Z as necessary.
A method for producing a fin material for a heat exchanger by hot rolling and cold rolling an alloy having r0.0'1 to 0.2% a and the remainder consisting of Al and unavoidable impurities, comprising: After the first cold rolling, 20
A first intermediate annealing is performed at a temperature of 0°C or higher and lower than the complete recrystallization temperature, then a second successive rolling is performed at a reduction rate of 5 to 65%, and then a temperature of at least the recrystallization temperature and 450°C or lower. 1. A method for producing a fin material for a heat exchanger, comprising performing a second intermediate annealing at a rolling reduction rate of 25 to 65%, followed by a third successive rolling at a rolling reduction ratio of 25 to 65%. (3) Mn 0.5-2.0 'I', SiO,1
~1% and optionally ZrO,01~0.
Al-Si alloy or Ad-Si alloy is used as a core material.
- In a method of manufacturing a plating sheet for a heat exchanger by hot rolling and cold rolling a laminated plate using Mg alloy as a skin material, after first rolling a hot-rolled plate of the laminated plate, The cold-rolled sheet is subjected to a first intermediate annealing at a temperature of 200"C or higher and lower than the complete recrystallization temperature, then subjected to a second successive rolling at a rolling reduction of 25 to 65%, and then further rolled at a temperature higher than the recrystallization temperature. A method for producing a plating sheet for a heat exchanger, characterized in that a second intermediate annealing is performed at a temperature of 450° C. or lower, followed by a third successive rolling at a rolling reduction ratio of 25 to 65%. (4) MnO,j~2. O%, Si0.1-1%
and Zn 0.2 to 2. O%, SnO,
Zr.
An alloy containing 0.01 to 0.2'% with the remainder being AA' and unavoidable impurities is used as a core material, and an Al-Si alloy or AAI'-8i-Mg alloy is used as a skin material, and the laminated plate is made of In the method of manufacturing a plating sheet for a heat exchanger by hot rolling and cold rolling, after subjecting the hot rolled plate of the laminated plate to first successive rolling,
The cold-rolled sheet is subjected to a first intermediate annealing at a temperature of 200°C or higher and lower than the complete recrystallization temperature, and then at a rolling reduction of 25 to 65 degrees. t' Perform two successive rollings, then perform a second intermediate annealing at a temperature above the recrystallization temperature and below 450"C, and perform a third successive rolling at a reduction rate of 25 to 65%. A method for producing a plating sheet for a heat exchanger, characterized in that: