JP2002030367A - Aluminum alloy brazing sheet excellent in strength and corrosion resistance for heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a brazing sheet excellent in strength and corrosion resistance and used as the member for structural purpose such as a heat exchanger. SOLUTION: This brazing sheet is obtained by using an Al alloy having a composition containing 0.1 to 1.8% Mn, if required, containing one or more kinds selected from 0.05 to 2.0% Si, 0.05 to 1.2% Cu and 0.05 to 1.5% Fe, if required, further containing one or more kinds selected from 0.03 to 0.5% Ti, 0.03 to 0.5% Zr and 0.03 to 0.05% Cr, and the balance Al with inevitable impurities as a core material, cladding a sacrificial anode surface material having a composition containing 0.5 to 2.5% Mg, 3.5 to 10.0% Zn, 0.05 to 0.5% Ti and 0.1 to 1.5% Mn, and the balance Al with inevitable impurities on one side of the core material and cladding an Al-Si based or Al-Si-Zr based brazing filler metal on the other side of the core material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aluminum alloy brazing sheet for a heat exchanger having excellent strength and pitting corrosion resistance, and more particularly to a tube material mainly used for a heat exchanger for a vehicle such as a radiator or a heater core. It relates to an aluminum alloy brazing sheet to be used.

[0002]

2. Description of the Related Art Conventionally, JIS 3003 Al-Mn has been used as a tube material for an automobile radiator or a heater core.
Aluminum alloy as a core material, and one side of this core material
-Si or Al-Si-Zn-based brazing material was clad, and the other surface of the core was clad with an Al-Zn-based aluminum alloy made of JIS 7072 lower than the core as a sacrificial anode skin material 3 A layer of aluminum alloy brazing sheet is used. This aluminum alloy brazing sheet has insufficient strength and corrosion resistance in an acidic environment and an alkaline environment, so that the heat exchanger required in recent years with low fuel consumption of automobiles has been reduced in weight, The requirements for high strength and thin wall of the required tube cannot be satisfied.

[0003] Various aluminum alloy brazing sheets have been proposed for increasing the strength and reducing the thickness of the tubes accompanying the weight reduction of the heat exchanger. For example, Japanese Patent Application Laid-Open
JP-A-209246 discloses that on one surface of an aluminum alloy core material, Ti: 0.05 to 0.3% having a lower potential than the core material,
n: 0.5 to 3%, Mg: 0.1 to 5%, and, if necessary, Ca: 0.05 to 0.3%;
Al-Zn containing 0.5 to 0.3% of one or two kinds
A cladding of a Ti-based alloy as a sacrificial anode material (however,% indicates mass%; the same applies hereinafter), and an Al-Si-based or Al-Si-Zn-based brazing material is coated on the other surface of the core material. An aluminum alloy brazing sheet formed by cladding is described. When this aluminum alloy brazing sheet is further thinned, the amount of Zn in the sacrificial anode skin material after brazing is insufficient, and there has been a problem that sufficient strength and corrosion resistance cannot be obtained.

[0004] For the same purpose, Japanese Patent No. 2,564,190 discloses that as a core material, Mg <0.1%, Mn: 0.2.
-1.5%, and if necessary, Cu: 0.5%
Hereinafter, an Al-Si-based or Al-Si-Zn-based brazing material is clad on one surface of an Al alloy core material containing one or more of Cr: 0.3% or less and Zr: 0.2% or less. And Mg: 0.3 on the other surface of the Al alloy core material.
An aluminum alloy brazing sheet clad with an Al alloy sacrificial anode skin material containing up to 2.5% and containing Zn: 2% or less is described, but this brazing sheet also has insufficient strength and corrosion resistance.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide an aluminum alloy brazing sheet which has sufficient strength even if it is made thinner and has further corrosion resistance.

[0006]

Means for Solving the Problems The present inventors have conducted research on an aluminum alloy brazing sheet having further excellent strength and corrosion resistance.
1.8%, and if necessary, Si: 0.05
To 2.0%, Cu: 0.05 to 1.2%, Fe: 0.0
One or more of 5 to 1.5% is contained, and the remainder is made of Al-Mn-based alloy or Al-Si-Z on one surface of an Al-Mn-based alloy core material composed of Al and unavoidable impurities.
An n-type brazing material is clad, and the other surface of the core material is
g: 0.5 to 2.5%, Zn: 3.5 to 10.0%, T
An aluminum alloy brazing sheet clad with a sacrificial anode skin material having a composition of i: 0.05 to 0.5%, Mn: 0.1 to 1.5%, and the balance of Al and unavoidable impurities, Since Mn is contained in both the core material and the sacrificial anode skin material, the strength is further improved. Further, since the sacrificial anode skin material contains a relatively large amount of Zn, the sacrificial anode action is promoted and the corrosion resistance is improved. Have been further improved, and in particular, the corrosion resistance to aqueous solutions in a wide pH range from a weakly acidic solution to an alkaline solution having a pH of 9 or more has been further improved.

The present invention has been made based on this finding, and (1) a core material comprising an Al alloy containing 0.1 to 1.8% of Mn and the balance of Al and unavoidable impurities. And Mg: 0.5 to 2.5% on one surface of the core material;
Zn: 3.5 to 10.0%, Ti: 0.05 to 0.5
%, Mn: 0.1 to 1.5%, and the rest is clad with a sacrificial anode skin material having a composition consisting of Al and unavoidable impurities, and the other surface of the core material is made of Al-Si or Al-
Aluminum alloy brazing sheet for heat exchanger excellent in strength and corrosion resistance formed by cladding a Si-Zn brazing material, (2) Mn: 0.1 to 1.8%, Si: 0.05
To 2.0%, with the balance being an Al alloy consisting of Al and unavoidable impurities, and Mg:
0.5 to 2.5%, Zn: 3.5 to 10.0%, Ti:
A sacrificial anode skin material having a composition of 0.05 to 0.5% and Mn: 0.1 to 1.5%, with the balance consisting of Al and unavoidable impurities, is clad, and the other surface of the core is made of Al. −
Aluminum alloy brazing sheet for heat exchangers having excellent strength and corrosion resistance obtained by cladding a Si-based or Al-Si-Zn-based brazing material, (3) Mn: 0.1 to 1.8
%, Cu: 0.05 to 1.2%, the balance being an Al alloy composed of Al and unavoidable impurities as a core material, and Mg: 0.5 to 2.5%, Zn on one surface of the core material. : 3.5-
10.0%, Ti: 0.05 to 0.5%, Mn: 0.1
~ 1.5%, the remainder being clad with a sacrificial anode skin material having a composition of Al and unavoidable impurities, and cladding an Al-Si-based or Al-Si-Zn-based brazing material on the other side of the core material. Aluminum alloy brazing sheet for heat exchanger with excellent strength and corrosion resistance, (4) M
n: 0.1 to 1.8%, Fe: 0.05 to 1.5%, the balance being an Al alloy composed of Al and unavoidable impurities, and Mg: 0 on one surface of the core material. 0.5-2.5
%, Zn: 3.5 to 10.0%, Ti: 0.05 to 0.
5%, Mn: 0.1 to 1.5%, the remainder is clad with a sacrificial anode skin material having a composition of Al and inevitable impurities, and the other surface of the core material is made of Al-Si or Al
-Aluminum alloy brazing sheet for heat exchanger having excellent strength and corrosion resistance formed by cladding a Si-Zn brazing material, (5) Mn: 0.1 to 1.8%, Si: 0.0
An aluminum alloy containing 5 to 2.0% and Cu: 0.05 to 1.2%, the remainder being Al and unavoidable impurities is used as a core material, and Mg: 0.5 to 2 0.5%, Z
n: 3.5 to 10.0%, Ti: 0.05 to 0.5%,
Mn: clad a sacrificial anode skin material having a composition containing 0.1 to 1.5%, with the balance consisting of Al and inevitable impurities,
An Al-Si-based or Al-Si
-Aluminum alloy brazing sheet for heat exchanger excellent in strength and corrosion resistance formed by cladding a Zn-based brazing material, (6) Mn: 0.1 to 1.8%, Cu: 0.05 to
A core material containing 1.2%, Fe: 0.05 to 1.5%, and the balance being Al and an unavoidable impurity;
On one surface of the core material, Mg: 0.5 to 2.5%, Zn:
3.5 to 10.0%, Ti: 0.05 to 0.5%, M
n: a sacrificial anode skin material having a composition containing 0.1 to 1.5% and the balance consisting of Al and inevitable impurities is clad, and the other surface of the core material is made of Al-Si or Al-Si-
Aluminum alloy brazing sheet for heat exchanger with excellent strength and corrosion resistance, clad with Zn-based brazing material,
(7) Mn: 0.1-1.8%, Si: 0.05-2.
0%, Fe: 0.05-1.5%, the remainder being Al
And an Al alloy composed of unavoidable impurities as a core material, and one surface of the core material has Mg: 0.5 to 2.5% and Zn: 3.5.
１10.0%, Ti: 0.05 to 0.5%, Mn: 0.
A sacrificial anode skin material having a composition of 1 to 1.5% and the balance of Al and unavoidable impurities is clad, and an Al-Si-based or Al-Si-Zn-based brazing material is coated on the other side of the core material. Aluminum alloy brazing sheet for heat exchanger with excellent strength and corrosion resistance formed by cladding, (8) M
n: 0.1 to 1.8%, Si: 0.05 to 2.0%, C
u: 0.05 to 1.2%, Fe: 0.05 to 1.5%, the remainder being an Al alloy comprising Al and unavoidable impurities as a core material, and Mg: 0 on one surface of the core material. 0.5-2.
5%, Zn: 3.5 to 10.0%, Ti: 0.05 to
0.5%, Mn: 0.1 to 1.5%, the remainder being A
1 and a heat exchange excellent in strength and corrosion resistance by cladding a sacrificial anode skin material having a composition of unavoidable impurities and a clad Al-Si-based or Al-Si-Zn-based brazing material on the other surface of the core material. Dexterous aluminum alloy brazing sheet.

According to the present invention, the core material constituting the aluminum alloy brazing sheet according to any one of the above (1) to (8) further comprises Ti: 0.03 to 0.5%, Z:
By containing one or more of r: 0.03 to 0.5% and Cr: 0.03 to 0.5%, the strength can be further improved. Therefore, the present invention contains (9) Mn: 0.1 to 1.8%, and further contains Tn.
i: 0.03 to 0.5%, Zr: 0.03 to 0.5%,
Cr: One or two or more of 0.03 to 0.5% is contained, and the remainder is made of an Al alloy composed of Al and unavoidable impurities, and Mg: 0.5 to 0.5% on one surface of the core. 2.5
%, Zn: 3.5 to 10.0%, Ti: 0.05 to 0.
5%, Mn: 0.1 to 1.5%, the remainder is clad with a sacrificial anode skin material having a composition of Al and inevitable impurities, and the other surface of the core material is made of Al-Si or Al
-Aluminum brazing sheet for heat exchanger having excellent strength and corrosion resistance obtained by cladding a -Si-Zn brazing material, (10) Mn: 0.1 to 1.8%, Si: 0. 1%.
0.05 to 2.0%, and further, Ti: 0.03 to 0.1%.
5%, Zr: 0.03 to 0.5%, Cr: 0.03 to
One or more of 0.5%, the balance being A
and an Al alloy comprising unavoidable impurities is used as a core material, and Mg: 0.5 to 2.5%, Zn: 3.
5 to 10.0%, Ti: 0.05 to 0.5%, Mn:
A sacrificial anode skin material having a composition of 0.1 to 1.5% and the balance consisting of Al and inevitable impurities is clad, and the other surface of the core material is made of Al-Si or Al-Si-Zn.
Aluminum alloy brazing sheet for heat exchangers with excellent strength and corrosion resistance obtained by cladding a brazing material, (1
1) Mn: 0.1 to 1.8%, Cu: 0.05 to 1.2
% Ti, 0.03-0.5%, Zr:
An aluminum alloy containing at least one of 0.03 to 0.5% and Cr: 0.03 to 0.5%, and the balance consisting of Al and unavoidable impurities; On one side, Mg: 0.5 to 2.5%, Zn: 3.5 to 10.0
%, Ti: 0.05 to 0.5%, Mn: 0.1 to 1.5
%, The balance being clad with a sacrificial anode skin material having a composition consisting of Al and unavoidable impurities, and cladding an Al-Si-based or Al-Si-Zn-based brazing material on the other surface of the core material. And an aluminum alloy brazing sheet for a heat exchanger having excellent corrosion resistance, (12) Mn: 0.
1 to 1.8%, Fe: 0.05 to 1.5%, Ti: 0.03 to 0.5%, Zr: 0.03 to 0.
5%, Cr: One or more of 0.03 to 0.5% of the alloy containing the remaining Al and unavoidable impurities is used as a core material, and Mg: 0.5
~ 2.5%, Zn: 3.5 ~ 10.0%, Ti: 0.0
5 to 0.5%, Mn: 0.1 to 1.5%, the remainder is clad with a sacrificial anode skin material having a composition of Al and unavoidable impurities, and the other surface of the core material is made of Al-Si. Alloy brazing sheet for heat exchangers excellent in strength and corrosion resistance obtained by cladding a brazing alloy or an Al-Si-Zn brazing material, (13) Mn: 0.1-1.8%, S
i: 0.05 to 2.0%, Cu: 0.05 to 1.2%, Ti: 0.03 to 0.5%, Zr: 0.
A core material containing an Al alloy containing at least one of 0.3% to 0.5% and Cr: 0.03% to 0.5%, and the balance consisting of Al and unavoidable impurities; And M
g: 0.5 to 2.5%, Zn: 3.5 to 10.0%, T
i: 0.05 to 0.5%, Mn: 0.1 to 1.5%, and the other side of the core material is clad with a sacrificial anode skin material having a composition consisting of Al and unavoidable impurities. To Al
-Si-based or Al-Si-Zn-based brazing material clad aluminum alloy brazing sheet for heat exchanger with excellent strength and corrosion resistance, (14) Mn: 0.1 to
1.8%, Cu: 0.05 to 1.2%, Fe: 0.05
-1.5%, and Ti: 0.03-0.5%
%, Zr: 0.03 to 0.5%, Cr: 0.03 to 0.
An aluminum alloy containing one or more of 5% of the alloy and the remainder consisting of Al and unavoidable impurities is used as a core material, and one surface of the core material has Mg: 0.5 to 2.5%, Zn: 3.5-
10.0%, Ti: 0.05 to 0.5%, Mn: 0.1
~ 1.5%, the remainder being clad with a sacrificial anode skin material having a composition of Al and unavoidable impurities, and cladding an Al-Si-based or Al-Si-Zn-based brazing material on the other side of the core material. Aluminum alloy brazing sheet for heat exchanger with excellent strength and corrosion resistance, (15) M
n: 0.1 to 1.8%, Si: 0.05 to 2.0%, F
e: 0.05 to 1.5%, and further Ti: 0.0
3 to 0.5%, Zr: 0.03 to 0.5%, Cr: 0.
One or two or more of the alloys are contained in a core material containing at least one of Al and Al and inevitable impurities, and Mg: 0.5 to 2.5% on one surface of the core material. %, Z
n: 3.5 to 10.0%, Ti: 0.05 to 0.5%,
Mn: clad a sacrificial anode skin material having a composition containing 0.1 to 1.5%, with the balance consisting of Al and inevitable impurities,
An Al-Si-based or Al-Si
-An aluminum alloy brazing sheet for heat exchanger having excellent strength and corrosion resistance obtained by cladding a Zn-based brazing material, (16) Mn: 0.1 to 1.8%, Si: 0.05
To 2.0%, Cu: 0.05 to 1.2%, Fe: 0.0
5 to 1.5%, and Ti: 0.03 to 0.5
%, Zr: 0.03 to 0.5%, Cr: 0.03 to 0.
An aluminum alloy containing one or more of 5% of the alloy and the remainder consisting of Al and unavoidable impurities is used as a core material, and one surface of the core material has Mg: 0.5 to 2.5%, Zn: 3.5-
10.0%, Ti: 0.05 to 0.5%, Mn: 0.1
~ 1.5%, the remainder is clad with a sacrificial anode skin material having a composition of Al and inevitable impurities, and clad an Al-Si-based or Al-Si-Zn-based brazing material on the other surface of the core material. An aluminum alloy brazing sheet for heat exchangers having excellent strength and corrosion resistance.

First, the reason why the component composition of the aluminum alloy brazing sheet for a heat exchanger of the present invention is limited as described above will be described. (A) Core material Mn: Mn is crystallized or precipitated and dispersed as an Al-Mn intermetallic compound in the core material matrix, improves the strength after brazing, makes the potential of the core material noble, and increases the sacrificial anode. It is a component that improves the pitting corrosion resistance not only from the skin material side but also from the brazing material side. If the content is less than 0.1%, the desired effect cannot be obtained. On the other hand, the content exceeds 1.8%. If it is contained, it is not preferable because workability is deteriorated due to formation of a coarse intermetallic compound. Therefore, the content of Mn is set to 0.1 to 1.8%. A more preferable range of the Mn content is 0.8 to 1.
5%.

Si: Si becomes an Al-Mn-Si intermetallic compound by coexisting with Mn, and is dispersed in a base material or solid-dissolved in a matrix to improve the strength of the core material. It reacts with Mg diffused from the sacrificial anode skin material to form Mg ₂ Si to improve the strength. However, if the content is less than 0.05%, the desired effect cannot be obtained. If the content exceeds 0.0%, the melting point of the core material is lowered, and the core material is undesirably melted during brazing. Therefore, the content of Si is set to 0.05 to 2.0%. A more preferable range of the content of Si is 0.4 to 1.2%.

Cu: Cu contained in the core material forms a solid solution in the matrix to improve the strength of the core material after brazing, and diffuses into the sacrificial anode skin material by brazing heat treatment, thereby electrochemically forming the core material. Has a function of improving the pitting corrosion resistance not only on the sacrificial anode skin material side but also on the brazing material side, but if the content is less than 0.05%, the desired effect cannot be obtained, If the content exceeds 1.2%, the corrosion rate becomes too fast, and particularly, the corrosion rate at the joint becomes too fast, which is not preferable. Therefore, the content of Cu is set to 0.05 to 1.2%. A more preferable range of the Cu content is 0.3 to 0.7%.

Fe: Fe is crystallized or precipitated in the matrix as an Al-Fe intermetallic compound, improves the strength after brazing, and is resistant to alkaline corrosion by the crystallized or precipitated Al-Fe metal. The inter-compound has the effect of improving the corrosion resistance in alkaline because it suppresses the progress of corrosion in the core material. However, if the content is less than 0.05%, the desired effect cannot be obtained. % Is not preferred because the rate of corrosion of the core material in the acid is too high. Therefore, the content of Fe is set to 0.05 to 1.5%.
A more preferred range for the Fe content is above 0.7 to 1.
3%.

[0013] Ti: Ti component after the brazing TiAl
_It is dispersed as a fine intermetallic compound such as 3 in the base material and has an effect of improving the strength of the core material. Therefore, it is added as necessary. However, if the content is less than 0.03%, a desired effect can be obtained. On the other hand, if it exceeds 0.5%, the workability is impaired, and furthermore, the corrosion resistance is reduced by a huge Ti-Al-based intermetallic compound, which is not preferable. Therefore, T
The content of i was set to 0.03 to 0.5%. A more preferable range of the Ti content is 0.07 to 0.25%.

Zr: Like Ti, Zr is also dispersed as a fine intermetallic compound such as ZrAl _{3 in the} base material after brazing and has an effect of improving the strength of the core material. If the content is less than 0.03%, the desired effect cannot be obtained. On the other hand, if the content exceeds 0.5%, processability is impaired, which is not preferable. Therefore, the content of Zr is set to 0.03 to 0.5%. A more preferable range of the Zr content is 0.07 to 0.25%.

Cr: Cr is also fine Al-
It is dispersed in the matrix as a Cr-based intermetallic compound and has the effect of improving the strength of the core material, and is added as necessary. However, if the content is less than 0.03%, the desired effect cannot be obtained. If it exceeds 0.5%, processability is impaired, which is not preferred. Therefore, the content of Cr is 0.03 to
It was set to 0.5%. A more preferable range of the Cr content is 0.07 to 0.25%.

(B) Sacrificial anode skin material Mg: Mg is dissolved in a matrix to improve strength, and is diffused from the core material or Si and Mg in the core material.
_Although it has the effect of improving the strength by forming 2Si, if its content is less than 0.5%, the desired corrosion resistance cannot be obtained, so it is not preferable. The effect of improving the strength cannot be obtained. Therefore, the content of Mg contained in the sacrificial anode skin material was set to 0.5 to 2.5%. A more preferable range of the Mg content is 0.7 to 1.8%.
It is.

Zn: Zn makes the potential of the sacrificial anode skin material base, forms a potential distribution effective for corrosion protection from the skin material surface to the core material by brazing heat treatment, improves the pitting corrosion resistance,
g and MgZn ₂ to form and have the effect of improving the strength. However, when the content is less than 3.5%, the sacrificial anode effect in an acidic solution does not work sufficiently, which is not preferable. on the other hand,
If Zn is contained in excess of 10.0%, the self-corrosion property becomes too fast and the workability deteriorates, which is not preferable. Therefore, the Zn content in the sacrificial anode skin material is 3.
It was set to 5 to 10.0% (more preferably 4.0 to 8.0%).

Ti: The Ti in the sacrificial anode skin material is dispersed as a fine intermetallic compound after brazing to improve the strength. Further, the light and shade layer of Ti formed in the rolling direction at the time of rolling has a corrosion form. Has a function of suppressing the occurrence of pitting corrosion, which causes corrosion to spread in a preferred layered form and shortens the life of the brazing sheet, but has a content of 0.05%
If it is less than the desired corrosion resistance, it is not preferable,
On the other hand, when the content exceeds 0.5%, the workability is lowered and the corrosion resistance is lowered due to the formation of the Al-Ti intermetallic compound, which is not preferable. Therefore, the content of Ti contained in the sacrificial anode skin material was determined to be 0.05 to 0.5%. A more preferable range of the Ti content is 0.07 to 0.1.
25%.

Mn: Mn in the sacrificial anode skin material is dispersed as an Al—Mn intermetallic compound in the base material to improve the strength and is dispersed against corrosion in an alkaline solution.
Corrosion is suppressed by the l-Mn-based intermetallic compound, and has an action of improving corrosion resistance. However, if the content is less than 0.1%, desired corrosion resistance cannot be obtained, which is not preferable. If the content exceeds 5%, rolling workability is deteriorated due to formation of coarse intermetallic compounds, which is not preferable. Therefore, the content of Mn contained in the sacrificial anode skin material was set to 0.1 to 1.5%. A more preferable range of the Mn content is 0.2 to 0.8%.

(C) Brazing material The brazing material used in the aluminum alloy brazing sheet for a heat exchanger of the present invention is a common Al-Si or A
There is no particular limitation as long as it is an l-Si-Zn-based brazing filler metal, but Si contained in the brazing filler metal is a component that lowers the melting point and imparts fluidity.
If the content is less than 15%, the desired effect cannot be obtained. On the other hand, if the content exceeds 15%, the fluidity is rather lowered, which is not preferable. Therefore, the content of Si in the brazing filler metal is 3 to 15%.
Determined. A more preferable range of the Si content in the brazing material is 5 to 12%. Further, the Al-Si-Zn-based brazing material is a material in which Zn is contained in the Al-Si-based brazing material in an amount of 1.0 to 5.0%.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION An Al alloy having a component composition shown in Table 1 is melted and cast to produce an ingot, and the ingot is homogenized under ordinary conditions. x was produced.

[0022]

[Table 1]

Further, an Al alloy having a component composition shown in Table 2 was melted and cast to produce an ingot. The ingot was homogenized under ordinary conditions, and then hot-rolled to a thickness of 50 mm. Sacrificial anode skin materials A to B made of a rolled plate were produced.

[0024]

[Table 2]

On the other hand, an Al alloy having a component composition shown in Table 3 is melted and cast to produce an ingot, and the ingot is subjected to hot rolling under ordinary conditions to be made of a hot-rolled sheet having a thickness of 50 mm. Materials I to II were produced.

[0026]

[Table 3]

The core materials a to x of Table 1, the sacrificial anode skin materials A to E of Table 2 and the brazing materials I to II of Table 3 were superimposed according to the combinations shown in Table 4, and the clad was formed by hot rolling. Then, after performing intermediate annealing, cold rolling is performed to obtain a brazing sheet of the present invention having a sheet thickness of 0.225 mm, a sacrificial anode cladding material and a brazing material having a cladding ratio of 10%, and a temper H14. Nos. 1 to 23 and conventional brazing sheets were produced. Using these brazing sheets 1 to 23 of the present invention and the conventional brazing sheet, respective test pieces were prepared, and these test pieces were
After holding at 0 ° C. for 3 minutes, cooling rate: 100 ° C./mi
n. Perform a heat treatment assuming brazing to cool to room temperature, then strength test and corrosion test 1 to the following conditions
2 was performed.

Tensile test A tensile test was conducted in accordance with the method specified in JIS H4000, and the measurement results are shown in Table 4.

The corrosion test 1 was prepared (acid resistance test) samples the brazing material side was obtained by coating with an adhesive of the specimen, further _{^{Cl -: 270ppm, SO 4 2-}} : 60p
An aqueous solution (pH: 3.4) containing pm, Fe ³⁺ : 30 ppm, Cu ²⁺ : 1 ppm and having a temperature of 80 ° C. was prepared as a corrosive liquid, and the sample was immersed and held in the corrosive liquid for 8 hours. Thereafter, an operation of applying a temperature cycle of dipping and holding in a static corrosion solution at room temperature for 16 hours was performed for 90 days, and 9 days.
The maximum corrosion depth from the surface of the sacrificial anode skin layer after 0 days was measured, and the measurement results are shown in Table 4.

The corrosion test 2 (alkali resistance _{^{test) Cl -: 270ppm, SO 4}} 2-: 60ppm, F
e ³⁺ : An aqueous solution containing 30 ppm was adjusted to pH 11 with NaOH. An aqueous solution at a temperature of 88 ° C. was prepared as a corrosive liquid.
Assuming that the sample is cooling water for an automotive heat exchanger, the flow rate is 0.7 m / sec. Temperature of flowing: After immersion and holding in a corrosive solution at 88 ° C. for 8 hours, a temperature cycle of immersing and holding in a static corrosion solution at room temperature for 16 hours is performed for 120 days, and after 120 days, The maximum corrosion depth from the surface of the sacrificial anode skin material layer was measured, and the measurement results are shown in Table 4.

[0031]

[Table 4]

From the results shown in Table 4, the brazing sheets 1 to 23 of the present invention are superior in strength to the conventional brazing sheets, and are excellent in corrosion resistance because the maximum corrosion depth from the surface is extremely small. You can see that.

[0033]

As described above, the brazing sheet of the present invention has higher strength and can be made thinner, and has excellent corrosion resistance. The heat exchanger is
It can be made even lighter and contributes to the improvement of fuel efficiency of automobiles, etc., and can be used for a long time without penetrating even if cooling water with a wide range of pH is used. It is.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masakazu Edo 85, Hiramatsu, Susono-shi, Shizuoka Prefecture Inside the Technology Development Center of Mitsubishi Aluminum Co., Ltd. Inside the Technology Development Center

Claims (3)

[Claims] 1. M% in mass% (hereinafter,% means mass%)
n: 0.1 to 1.8%, the balance being an Al alloy consisting of Al and unavoidable impurities as a core material; Mg: 0.5 to 2.5% on one surface of the core material;
5 to 10.0%, Ti: 0.05 to 0.5%, Mn:
A sacrificial anode skin material having a composition of 0.1 to 1.5% and the balance of Al and unavoidable impurities is clad, and the other surface of the core material is made of Al-Si or Al-Si.
-An aluminum alloy brazing sheet for a heat exchanger having excellent strength and corrosion resistance, characterized by being clad with a Zn-based brazing material. 2. Mn: 0.1-1.8%, Si: 0.05-2.0%, Cu: 0.05-1.
2%, Fe: One or two or more of 0.05 to 1.5%, and the rest is an Al alloy comprising Al and unavoidable impurities as a core material, and Mg: 0.5-2.5%, Zn:
3.5 to 10.0%, Ti: 0.05 to 0.5%, M
n: clad a sacrificial anode skin material having a composition of 0.1 to 1.5%, with the balance consisting of Al and unavoidable impurities, and Al-Si or Al-Si on the other surface of the core material.
-An aluminum alloy brazing sheet for a heat exchanger having excellent strength and corrosion resistance, characterized by being clad with a Zn-based brazing material. 3. The method according to claim 1, wherein the core material further comprises Ti: 0.03 to 0.1.
5%, Zr: 0.03 to 0.5%, Cr: 0.03 to
The aluminum alloy brazing sheet for heat exchangers having excellent strength and corrosion resistance according to claim 1 or 2, which comprises one or more of 0.5%.