JPH0797652A - Production of aluminum alloy brazing sheet fin material and heat exchanger made of aluminum alloy - Google Patents

Abstract

PURPOSE:To produce a brazing sheet fin material free from buckling and deterioration in thermal efficiency and a heat exchanger made of aluminum alloy. CONSTITUTION:This brazing sheet fin material can be produced by using an aluminum alloy, having a composition consisting of, by weight, >0.03-1.2% Si, >0.05-2.0% Fe, and the balance aluminum with inevitable impurities, as a core material and cladding both sides with an aluminum alloy brazing filler metal having a composition consisting of, by weight, >7.0-12.0% Si, >0.1-8.0% Cu, one or >=2 kinds among >0.5-6.0% Zn, >0.002-0.3% In, and >0.002-0.3% Sn, and the balance aluminum with inevitable impurities. At the time of producing a heat exchanger by using this brazing sheet, brazing heating temp. is regulated to 570-585 deg.C.

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 fin material and an aluminum alloy heat exchanger. More specifically, an aluminum alloy heat exchanger having excellent thermal efficiency is manufactured by a brazing method. A brazing sheet fin material for manufacturing and a brazing method for manufacturing an aluminum alloy heat exchanger using the fin material.

[0002]

2. Description of the Related Art Heat exchangers include serpentine type condensers and laminated type evaporators. FIG. 1 is a perspective view of a partial cross section of a serpentine type capacitor. In this capacitor, a tube 1 (multi-hole tube) extruded hot or warm is bent in a meandering shape,
Corrugated fins 2 are brazed between the tubes 1. Here, 3 indicates a connector. In tube 1
JIS-3003 alloy or the like is used. For the corrugated fin 2, for example, JIS-4045 alloy or JI can be used on both sides of the core of JIS-3003 alloy.
A brazing sheet in which a brazing material such as S-4343 alloy is clad is used. For the core, an alloy obtained by adding Zn to JIS-3003 alloy to give a sacrificial anode effect is also used. For brazing, a flux brazing method, a Nocolock brazing method using a non-corrosive flux, or the like is used. Brazing is performed by heating to about 600 ° C.

In recent years, as part of the weight reduction of automobiles, the heat exchanger constituent members have been made thinner. In order to reduce the thickness of the fin material, it is necessary to increase the alloy concentration of the core to increase the strength. However, increasing the alloy concentration lowers the melting point.
There was a risk that the fin material would melt during the brazing process of heating to about 00 ° C. Even if it did not melt, the fin material buckled more frequently during the brazing process. When the fin material buckled, the ventilation deteriorated and the performance of the heat exchanger deteriorated. Further, a large amount of the intermetallic compound deposited on the core dissolved during the brazing process to deteriorate the thermal conductivity of the core. Wax diffused to the core and accelerated the lowering of the melting point of the alloy. The above-mentioned melting and buckling of the fins, or a decrease in thermal conductivity becomes more prominent as the fin material becomes thinner. Therefore, the brazing sheet fin material is normally manufactured at 140 μm and the bare fin material is manufactured at 80 μm.

By the way, a low-temperature brazing material for lowering the heating temperature during brazing has an Al-20% Z melting point of about 500.degree.
Although n alloys and Zn alloys are known, they have not been put to practical use in heat exchangers because the brazing easily corrodes after brazing. Also Al-Zn
When the Zn content of the alloys exceeds 8%, the rolling workability deteriorates, making it impossible to produce a brazing sheet in which the core and the braze are rolled together. Japanese Unexamined Patent Publication (Kokai) No. 3-57588 discloses a low melting point brazing material for castings, but since it contains a large amount of Cu and Zn in excess of 8% and is poor in workability, it is used exclusively for brazing. Thus, the industrial manufacturing method of the brazing sheet for low temperature brazing has not been established.

[0005]

In view of this, the present invention has good rolling workability, does not melt or buckle during the brazing process, and the intermetallic compound forms a solid solution to provide a thermal conductivity. The invention is to develop a brazing sheet fin material that does not lower the temperature and a method for manufacturing an aluminum alloy heat exchanger using the fin material. That is, the invention of claim 1 is
Si over 0.03 wt% and 1.2 wt% or less, 2.0 wt% over 0.05 wt%
The core is an aluminum alloy containing the following Fe and the balance aluminum and unavoidable impurities, and 7.0 wt% on both sides.
Over 12.0 wt% Si, over 0.1 wt% 8.0 wt% Cu
Containing 0.5% to more than 6.0% by weight of Zn, 0.002% to more than 0.3% by weight of In, and more than 0.002% to less than 0.3% of Sn by one or more types. A brazing sheet fin material clad with an aluminum alloy brazing material composed of the balance aluminum and unavoidable impurities.

The invention of claim 2 is more than 0.03 wt% and 1.2 w
Containing Si of t% or less, Fe of more than 0.05 wt% and 2.0 wt% or less,
Zn over 0.05 wt% and 5.0 wt% or less, 0.3 wt% over 0.002 wt%
The following In, more than 0.002 wt% and 0.3 wt% or less of Sn, one or more Sn is contained, and the balance is aluminum alloy consisting of aluminum and unavoidable impurities.
Contains 0 wt% to 12.0 wt% Si, 0.1 wt% to 8.0 wt% Cu, 0.5 wt% to 6.0 wt% Zn, 0.002 wt%
Over 0.3 wt% In, 0.002 wt% over 0.3 wt% Sn
It is a brazing sheet fin material containing one or more of the above and clad with an aluminum alloy brazing material consisting of the balance aluminum and unavoidable impurities.

The invention of claim 3 is more than 0.03 wt% and 1.2 w
Containing Si of t% or less, Fe of more than 0.05 wt% and 2.0 wt% or less,
Mg over 0.03 wt% and under 0.5 wt%, 0.6 wt% over 0.03 wt%
Mn below, Ni above 0.05 wt% and below 2.0 wt%, Cr below 0.03 wt% and below 0.3 wt%, Zr above 0.03 wt% and below 0.3 wt%,
An aluminum alloy that contains one or two or more kinds of Ti exceeding 0.03 wt% and 0.3 wt% or less and the balance aluminum and unavoidable impurities is the core, and exceeds 7.0 wt% on both sides.
Contains 12.0wt% or less Si, 0.1wt% to 8.0wt% or less Cu, 0.5wt% to 6.0wt% or less Zn, 0.002wt% to 0.3w
A brazing sheet fin material containing 1% or more of Sn of less than t% and Sn of more than 0.002 wt% and less than 0.3 wt%, and clad with an aluminum alloy brazing material composed of the balance aluminum and unavoidable impurities. .

Further, the invention of claim 4 is more than 0.03 wt% and 1.2 w
Containing Si of t% or less, Fe of more than 0.05 wt% and 2.0 wt% or less,
Zn over 0.05 wt% and 5.0 wt% or less, 0.3 wt% over 0.002 wt%
The following In, more than 0.002wt% and 0.3wt% or less of Sn containing 1 type or 2 types or more, 0.03wt% more than 0.5wt% or less Mg, more than 0.03wt% more than 0.6wt% less Mn, Ni exceeding 0.05 wt% and 2.0 wt% or less, Cr exceeding 0.03 wt% and 0.3 wt% or less,
Zr more than 0.03 wt% and 0.3 wt% or less, more than 0.03 wt% and 0.3 wt%
An aluminum alloy containing 1 or 2 or more of the following Ti, with the balance aluminum and unavoidable impurities as the core, and Si on both sides of more than 7.0 wt% and 12.0 wt% or less, 0.
Contains more than 1 wt% and less than 8.0 wt% Cu and more than 0.5 wt% and 6.0 w
Zn below t%, In over 0.002wt% and below 0.3wt%, 0.002wt%
Is a brazing sheet fin material containing at least one Sn alloy of 0.3 wt% or more and 0.3 wt% or less, and clad with an aluminum alloy brazing alloy composed of the balance aluminum and unavoidable impurities.

According to a fifth aspect of the present invention, when a heat exchanger is manufactured using the brazing sheet fin material according to the first aspect, the brazing heating temperature is set to 570 ° C to 585 ° C. It is a manufacturing method of an exchanger. The invention according to claim 6 is characterized in that, when a heat exchanger is manufactured using the brazing sheet fin material according to claim 2, the brazing heating temperature is set to 570 ° C to 585 ° C. The invention of claim 7 is characterized in that, when a heat exchanger is manufactured using the brazing sheet fin material of claim 3, the brazing heating temperature is set to 570 ° C to 585 ° C. According to the invention of claim 8, in manufacturing a heat exchanger using the brazing sheet fin material of claim 4, the brazing heating temperature is 570 ° C to 585 ° C.
It is characterized in that it is set to ° C.

First, the concept of the present invention will be described.
When an aluminum alloy heat exchanger is manufactured by the brazing method as described above, the heating is usually performed at a temperature near 600 ° C. Since the temperature of 600 ° C. is considerably high for the fin material, the fin material thinned with high strength has the following two problems. That is, the fin material buckles during heating, and the intermetallic compound in the alloy is re-dissolved to reduce the thermal conductivity of the fin material. The inventors have made earnest studies to solve these problems, and thought that it would be effective to lower the brazing heating temperature, and examined what temperature below this temperature could solve such a problem. As a result, it has been found that if the temperature is 585 ° C. or lower, buckling of fins during brazing is less likely to occur, and a decrease in thermal conductivity can be suppressed.

The above two points will be described in more detail. Buckling of the fins during heating is mainly caused by the high temperature creep of the fins, and this creep occurs rapidly at high temperatures around 590 ° C and above. Therefore, buckling due to creep does not occur at temperatures below 585 ° C. Another cause of buckling is that the brazing material diffuses into the fin and the melting point of the fin material decreases.
Then, the diffusion of the brazing occurs abruptly at a temperature higher than that around 595 ° C, and at the temperature of 585 ° C or less, the diffusion of the brazing hardly occurs and buckling of the fin material does not occur. The thermal conductivity of the fin material to be brazed is lowered because the intermetallic compound precipitated in the aluminum alloy is re-dissolved by heating during brazing. The higher the heating temperature, the wider the solid solubility limit of alloying elements and the faster the diffusion rate.
Re-dissolution becomes easy to occur. Therefore, lowering the heating temperature during brazing is effective in increasing the thermal conductivity of the fins. When the brazing temperature is 585 ° C or less, re-dissolution becomes difficult to occur, and the decrease in heat conductivity of the fin is prevented.

Here, the alloy composition of the core of the brazing sheet fin material of the present invention is S of more than 0.03 wt% and 1.2 wt% or less.
i, an aluminum alloy containing more than 0.05 wt% and less than 2.0 wt% Fe and the balance aluminum and unavoidable impurities, and Zn containing more than 0.05 wt% and less than 5.0 wt% Zn.
Alloys containing more than 002 wt% and 0.3 wt% or less In, and 0.002 wt% or more and 0.3 wt% or less Sn and alloys containing 0 or more and 0.
Mg over 03 wt% and 0.5 wt% or less, Mg over 0.03 wt% and 0.6 wt% or less, Ni over 0.05 wt% and 2.0 wt% or less, Cr over 0.03 wt% and 0.3 wt% or less, 0.03 wt% More than 0.3 wt% Zr,
It is an aluminum alloy to which one or more of Ti of more than 0.03 wt% and 0.3 wt% or less has been added. The composition of the core of the fin material of the present invention is conventionally known.

The role of the alloying element of the core and the reason for its limitation will be described below. Si contributes to the strength improvement. That amount
If it is less than 0.03 wt%, no effect is obtained, and if it exceeds 1.2 wt%, it melts even at the brazing temperature of the present invention. Fe forms an intermetallic compound and contributes to strength improvement. The amount is 0.05wt%
Below is not effective, and if it exceeds 2.0 wt%, the recrystallized grains of the fin become fine during brazing, and as a result, the diffusion of the brazing becomes large and the fin is easily crushed. Zn, In, and Sn are elements added to give the fin material a sacrificial anode effect. 0.05
If the Zn content is less than wt%, the In content is less than 0.002 wt%, and the Sn content is less than 0.002 wt%, the above effect cannot be sufficiently obtained.
If In exceeding t% or Sn exceeding 0.3 wt% is added, the thermal conductivity decreases. Mg, Mn, Ni, Cr, Zr and Ti are elements added to further improve the strength. Mg less than 0.03wt%,
Mn, Ni less than 0.05 wt%, Cr, Zr, Ti less than 0.03 wt% have no effect, and Mg exceeding 0.5 wt% reduces brazing property, and Mn exceeding 0.6 wt% has thermal conductivity. When Ni exceeds 2.0 wt% and Cr, Zr, and Ti exceed 0.3 wt%, the formability is deteriorated and the fin corrugation becomes difficult. Therefore, the addition amounts of these elements are determined within the above range. However, the lower limit of Ti is 0.03 wt% for improving strength, but 0.001 wt% is the lower limit when added for refining the ingot structure. Inevitable impurities in this alloy include B, which is added for refining the structure of the ingot, and these elements may be present as long as the amount is 0.03 wt% or less.

Next, the brazing material for clad on both sides of the core will be described. Wax is more than 7.0 wt% and less than 12.0 wt%
Si, containing more than 0.1 wt% and less than 8.0 wt% Cu, Zn more than 0.5 wt% and less than 6.0 wt%, In more than 0.002 wt% and less than 0.3 wt%, In.
It is an aluminum alloy that contains one or two or more of Sn in an amount of more than 002 wt% and 0.3 wt% or less, with the balance aluminum and unavoidable impurities. The clad ratio of the brazing material in the fin material is usually about 3% to 20%.

The role of the alloy composition of braze and the reason for limitation will be described below. Si lowers the melting point of wax. If the amount is 7.0 wt% or less or exceeds 11.0 wt%, the melting point becomes high, and brazing cannot be performed at a temperature of 585 ° C or less. Cu
It lowers the melting point of wax and improves the fluidity of wax. In addition, Cu is used as a refrigerant passage component (tube or brazing sheet).
To improve the external corrosion resistance of the heat exchanger when using an alloy containing Cu. That is, if Cu is not contained in the braze, Cu in the refrigerant passage constituent member diffuses into the braze during the brazing process, forming a low Cu region near the boundary between the braze and the passage constituent member, which preferentially exists. It becomes corroded with swelling. In the present invention, by adding Cu to the braze, the diffusion of Cu from the passage constituting member to the braze is prevented and the corrosion resistance is improved. Here, if the amount of Cu is 0.1 wt% or less, the effect is not sufficiently obtained, and if it exceeds 8.0 wt%, the brazing potential becomes too noble and the refrigerant passage constituent members are preferentially corroded. In addition, rolling workability also decreases. Therefore, Cu is more than 0.1 wt% and 8.0 wt% or less. Particularly, it shows stable characteristics at 0.5 to 3.5 wt%.

As described above, Cu suppresses external corrosion accompanied by swelling, but it has a drawback that pit-like external corrosion progresses at a high speed in the core because it makes the potential of the wax nobler than the core. Therefore, Zn is added to bring the brazing potential closer to the core potential to improve the corrosion resistance of the refrigerant passage constituting member. The amount is 0.
If it is 5 wt% or less, a sufficient effect cannot be obtained, and if it exceeds 6.0 wt%, the self-corrosion resistance of the brazing is reduced and the rolling workability is deteriorated.
In and Sn are also added for the same purpose as Zn. That is, the potential of the wax is made base and the corrosion resistance of the refrigerant passage constituting member is improved. If the amount is 0.002 wt% or less, sufficient effect cannot be obtained, and 0.3 wt%
If it exceeds, rolling workability is deteriorated. Fe may be contained as an unavoidable impurity in the wax as long as it is 1.0 wt% or less. However, Fe forms an intermetallic compound when the brazing material solidifies, and this intermetallic compound becomes the starting point of corrosion. Therefore, it is desirable that the Fe content be 0.5 wt% or less. Inevitable impurities other than Fe may be contained as long as each is 0.05 wt% or less.

The brazing sheet fin material of the present invention is used in an aluminum alloy heat exchanger manufactured by brazing. The aluminum alloy heat exchanger referred to here includes, but is not limited to, a radiator, a condenser, an evaporator and the like. In the present invention, the alloy composition of the fin material is limited as described above, but the composition of the aluminum alloy member (refrigerant passage constituent member, etc.) other than the fin material is not particularly limited, and brazing is performed at a temperature near 600 ° C. Alloys for use (for example, 1000 series alloys and 3000 series alloys with aluminum added 1.2 wt% or more) can be applied as they are. This is because the fin material of the present invention can be brazed at a temperature of 585 ° C. or lower, and buckling of the fin and deterioration of thermal conductivity cannot be worse than when brazing is performed at a high temperature of about 600 ° C.

In the method of the present invention, the brazing temperature is 570 ° C.
The reason for limiting the temperature to ˜585 ° C. is that if the temperature is lower than 570 ° C., the wax does not melt and cannot be brazed. If the temperature exceeds 585 ° C, the fin material may be melted or buckled, or the intermetallic compound may be re-dissolved to reduce the thermal conductivity of the fin. Further, the lowering of the brazing temperature has the secondary effects of extending the life of the brazing furnace and improving the corrosion resistance of the refrigerant passage constituting members. In the method of the present invention, the heat exchanger can be manufactured under the same conditions as the conventional one except for the brazing temperature. Further, any brazing method such as a flux brazing method or a Nocolock brazing method using a non-corrosive flux can be applied. Assembly, cleaning, flux application, etc. before brazing may be performed as usual. In this case, the flux can be brazed in the temperature range of the present invention by using, for example, a cesium-based flux. In the present invention, the process after brazing is not particularly limited. As usual, aging treatment, flux removal,
Processes such as painting are performed. The brazing sheet fin material of the present invention can be manufactured by manufacturing a ingot by a semi-continuous casting method, and hot rolling (combined rolling), cold rolling and annealing. It can also be manufactured in the processes of continuous casting and rolling, cold rolling and annealing.

[0019]

EXAMPLES The present invention will be specifically described below with reference to examples. Example 1 A brazing sheet fin material having an alloy composition shown in Tables 1 to 4 was produced. The fin has a plate thickness of 0.11 mm, and is a H14 tempered material in which 10% of brazing material is clad on both sides of the core. A sample was cut out from the obtained fin material and heated to various temperatures in nitrogen gas to perform a hanging test. In the hanging test, the protruding length was 50 mm. Also, the electrical conductivity of the samples after heating at various temperatures was measured. Regarding the conductivity of the clad fin, since the clad fin is on the surface of the braze and the cross-sectional area of the fin after brazing cannot be measured accurately, the bare fin of the same composition as the core is subjected to the same heating and the conductivity of the clad fin is measured. I used it as a substitute. It is known that the conductivity of the clad fin shows a tendency almost corresponding to the conductivity of the bare fin having the same composition as the fin core. The electrical conductivity is an index of thermal conductivity, and if the electrical conductivity of the fin is improved by 5% IACS, the thermal efficiency of the heat exchanger is improved by about 1%. The results are shown in Tables 5 and 6.

[0020]

[Table 1]

[0021]

[Table 2]

[0022]

[Table 3]

[0023]

[Table 4]

[0024]

[Table 5]

[0025]

[Table 6]

As is clear from Tables 5 and 6, the products of the present invention (Nos. 1 to 34) were excellent in both drooping property and electrical conductivity. This is because the melting point of the brazing filler metal of the clad fin was low, and therefore the test temperature was set to a low temperature. On the other hand, comparative example products (35 to 62,6
4,65) and the conventional products (No 66, 67) were poor in both drooping property and conductivity. This is because the melting point of the brazing filler metal of the clad fin is high, and the test temperature was set high to 600 ° C. or 610 ° C. which is the melting point of the brazing filler metal. In Comparative Example No. 63, brazing Cu and Zn were added in an amount exceeding the range of the present invention, and rolling cracks occurred, and it could not be processed into a brazing sheet.

[0027]

[Table 7]

[0028]

[Table 8]

Example 2 A fin material having the composition shown in Table 7 and a tube material were combined to assemble the capacitor shown in FIG. The fin material is a brazing sheet fin material having a thickness of 0.12 mm obtained by hot rolling and cold rolling an ingot, and the tube material is a multi-hole tube having a width of 16.0 mm manufactured by extrusion. The assembled capacitor was applied with a 10% solution of a flux prepared by mixing 3% of cesium-based flux with potassium fluoride-based flux and brazing by heating in nitrogen gas. With respect to the obtained capacitor, the appearance of crushing of fins and brazing property was observed.
Also, the tensile strength of the tube was measured. Further, the heat efficiency of the properly brazed capacitor was measured according to JIS-D-1618 (Testing method for air conditioners for automobiles). The thermal efficiency is shown in comparison with the conventional heat exchanger. The results are shown in Table 8 together with the materials and heating conditions.

As is clear from Table 8, the product No.
Had no crushing of the fins, good brazability, and excellent thermal efficiency. An aluminum alloy containing 1.2 wt% or more of Si was used for the tube, but high strength was maintained without melting. On the other hand, No.
Uses a conventional braze for brazing, and the brazing temperature is 600 ° C.
However, the thermal efficiency was hardly improved. In addition, No. of the comparative example product uses aluminum alloy with 1.2 wt% or more of Si for the tube, and the brazing temperature is 600 ° C.
It melted because it was hot.

[0031]

As described above, according to the present invention, brazing of the brazing sheet fin material has a low melting point, so brazing can be performed at a low temperature, and therefore, the fin material causes buckling and a decrease in thermal conductivity. It is possible to reduce the thickness and strength of the fin material without doing so, and it has a remarkable effect in reducing the size and weight of the heat exchanger.

[Brief description of drawings]

FIG. 1 is a perspective view of a partial cross section showing a serpentine type capacitor.

[Explanation of symbols]

 1 Flat tube 2 Fins 3 Connector

Claims (8)

[Claims] 1. Si of more than 0.03 wt% and 1.2 wt% or less, 0.05 w
An aluminum alloy that contains more than t% and less than 2.0 wt% Fe and the balance aluminum and unavoidable impurities is the core, and Si on both sides is more than 7.0 wt% and less than 12.0 wt%, and more than 0.1 wt% is more than 8.0 wt. % Cu or less and more than 0.5 wt% and 6.0 wt% or less
Zn, more than 0.002 wt% and 0.3 wt% or less In, more than 0.002 wt% 0.
A brazing sheet fin material containing 1% or 2 or more kinds of Sn of 3 wt% or less and clad with an aluminum alloy brazing material composed of the balance aluminum and unavoidable impurities. 2. Si of more than 0.03 wt% and 1.2 wt% or less, 0.05 w
Contains more than t% and less than 2.0wt% Fe and more than 0.05wt% and 5.0w
Zn below t%, In over 0.002wt% and below 0.3wt%, 0.002wt%
More than 0.3wt% and less than 0.3wt% of Sn, containing 1 type or 2 types or more, with aluminum alloy consisting of the balance aluminum and unavoidable impurities as core, and more than 7.0wt% over 12.0wt%
The following Si, containing more than 0.1wt% and less than 8.0wt% Cu, 0.5w
Zn over t% and 6.0 wt% or less, over 0.002 wt% and 0.3 wt% or less
In, 1 type or 2 of Sn exceeding 0.002wt% and 0.3wt% or less
A brazing sheet fin material clad with an aluminum alloy brazing material containing at least one kind and the balance aluminum and unavoidable impurities. 3. Si of more than 0.03 wt% and 1.2 wt% or less, 0.05 w
Contains more than t% and less than 2.0 wt% Fe and more than 0.03 wt% and 0.5 w
t% or less Mg, 0.03 wt% or more and 0.6 wt% or less Mn, 0.05 wt%
Over 2.0 wt% Ni and over 0.03 wt% 0.3 wt% C
r, 0.03 wt% to 0.3 wt% or less Zr, 0.03 wt% to 0.3
An aluminum alloy containing 1% or more of Ti of less than wt% and the balance of aluminum and unavoidable impurities is used as a core.
i, containing Cu of more than 0.1 wt% and 8.0 wt% or less, Zn of more than 0.5 wt% and 6.0 wt% or less, In of more than 0.002 wt% and 0.3 wt% or less, 0.
A brazing sheet fin material clad with an aluminum alloy brazing material which contains one or more Sn of more than 002 wt% and 0.3 wt% or less, and the balance aluminum and unavoidable impurities. 4. Si of more than 0.03 wt% and 1.2 wt% or less, 0.05 w
Contains more than t% and less than 2.0wt% Fe and more than 0.05wt% and 5.0w
Zn below t%, In over 0.002wt% and below 0.3wt%, 0.002wt%
More than 0.3 wt% and less than or equal to 0.3 wt% Sn, and more than 0.03 wt% and less than 0.5 wt% Mg, 0.03 wt%
Over 0.6 wt% Mn, over 0.05 wt% N under 2.0 wt%
i, Cr over 0.03 wt% and 0.3 wt% or less, 0.3 over 0.03 wt%
1% of Zr below wt% and Ti above 0.03 wt% and below 0.3 wt%
, Or 2 or more kinds, with an aluminum alloy consisting of the balance aluminum and unavoidable impurities as the core, Si on both sides of more than 7.0 wt% and 12.0 wt% or less, Si over 0.1 wt% and 8.0 wt%
Zn containing less than 0.5 wt% and less than 6.0 wt%, 0.00
Brazing of aluminum alloy brazing material containing 1% or 2 or more of In of more than 2 wt% and less than 0.3 wt% and Sn of more than 0.002 wt% and less than 0.3 wt% with the balance aluminum and unavoidable impurities. Sheet fin material. 5. A method of manufacturing an aluminum alloy heat exchanger, wherein a brazing heating temperature is set to 570 ° C. to 585 ° C. when manufacturing a heat exchanger using the brazing sheet fin material according to claim 1. . 6. A method for manufacturing an aluminum alloy heat exchanger, wherein a brazing heating temperature is set to 570 ° C. to 585 ° C. in manufacturing a heat exchanger using the brazing sheet fin material according to claim 2. . 7. A method for manufacturing an aluminum alloy heat exchanger, wherein a brazing heating temperature is set to 570 ° C. to 585 ° C. when manufacturing a heat exchanger using the brazing sheet fin material according to claim 3. . 8. A method for manufacturing an aluminum alloy heat exchanger, wherein a brazing heating temperature is set to 570 ° C. to 585 ° C. when manufacturing a heat exchanger using the brazing sheet fin material according to claim 4. .