JPH01246380A - Aluminum-alloy clad material for heat exchanger member - Google Patents

Abstract

PURPOSE:To improve the strength, corrosion resistance, etc., of the title clad material to be obtained by using an Al alloy with a specific composition as a cladding material and cladding at least one side of a core material of Al alloy having an electric potential nobler than that of the above, cladding material with this cladding material. CONSTITUTION:An alloy having a composition consisting of, by weight, 0.05-5% Ni, 0.3-10% Zn, 0.01-5% Mg, further one or more kinds among 0.001-0.5% Cr, 0.001-0.3% Zr, 0.001-1.5% Hf, 0.001-0.5%, Ti, and 0.0001-0.1% B, and the balance Al with inevitable impurities is used as a cladding material. Subsequently, at least one side of a core material consisting of an alloy of Al-Mn type, etc., having an electric potential nobler by >=50mV than the above cladding material is clad with the above cladding material, by which a clad material is prepared. If necessary, one side of the core material is clad with the above cladding material, and further, the other side is clad with an Al-alloy brazing filler metal containing >=5% Si, and/or Cu is further added by 0.05-2% to the composition of the above cladding material.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention mainly relates to an Al alloy composite material for heat exchanger members manufactured by a brazing method, which has particularly excellent strength.

[Prior Art] Many of conventional heat exchangers, especially automobile heat exchangers such as radiators, heaters, oil coolers, evaporators for air conditioners, condensers, etc., are made of Al alloy, and are assembled mainly by the waxing method. It is being The aluminum material for these heat exchangers is JIS 1, which is industrially pure aluminum.
000 series or JIS 300 with added Mn or Mg
A plating sheet is used in which one or both sides are clad with a brazing filler metal of an Al-8i type alloy and a core material made of a 0 type alloy or these alloys. Furthermore, in the case of radiator tubes and header materials, a sacrificial layer with a lower potential than the core material is provided on the surface of the plating sheet that comes into contact with water (liquid) to improve the corrosion resistance inside the interior through which cooling water (coolant) flows. Materials that prevent pitting corrosion are also used.

[Problem to be solved by the invention]

Recently, in order to reduce the weight and cost of heat exchangers, there has been an increasing demand for thinner various constituent members, and therefore materials with higher strength are required.

Therefore, attempts have been made to develop various alloys to meet these demands. However, heat exchanger components, especially by the wax method! ! ! The wax added heat property (approximately 6
00℃) and strength after brazing are both required to be high, and in the method of using 7 lux for brazing properties, there are requirements such as no reaction with flux and corrosion resistance after brazing. Therefore, there is a need to combine various performances. There is also a method of improving the corrosion resistance of structural members by using a sacrificial layer of a skin material made of an alloy that has a more base potential than the core material.
JIS 7072 alloy metal or Al added about wt%
ln on the base material.

An alloy whose potential is made less noble by adding Sn is used. However, these sacrificial materials have low strength, and a laminated material in which at least one side is clad with these alloys has the disadvantage that its strength is inevitably low as a result.

(Means for Solving the Problems) In view of this, the present invention has been made based on a wide and detailed study of the alloy composition of the A!!-Zn-Mg based alloy. We have developed an Al alloy composite material for heat exchanger parts that also has excellent strength.

That is, one of the present invention is Ni 0.05 to 5 wt%.

Zn0.3-10wt%, Mg0.01-5wt%
Contains Cr0.001-0.5 wt%, Z
r0.001~0.3wt%, l-1f0.001
~1.5 wt%, T i 0.001 ~ 0.5 w
t%, 30.0001 to 0.1 wt% of any one type or two or more types, and the remainder is 1 and unavoidable impurities as a skin material, and from the skin material 5.
Another feature of the present invention is that at least one side of a core material made of an Al alloy having a potential of 0 mV or more is clad, and another aspect of the present invention is Ni 0.05 to 5 wt%.
, Zn0.3~10wt%, M20.01~5w
t%, and further contains Cr0.001 to 0.5 wt%,
Z r0.001-0.3 wt%.

)1 f 0.001-1.5 wt%, T i 0
．． 001-0.5 wt%.

30,0001 to 0.1 wt% of any one or two or more types, and the remainder is Al and unavoidable impurities as a skin material, which has a potential 50 mV or more higher than that of the skin material. It is characterized in that one side of a core material made of an Al alloy is clad, and the other side is further clad with an Al alloy brazing filler metal containing 5 wt% or more of Si.

Furthermore, another one of the present invention is Ni0.05 to 5 wt%.

z n0.3~iowt%, fVl0.01~5wt
%, Cu0.05 to 2 wt%, and further Cr0.05 to 2 wt%.
001~0.5wt%, Zr0.001~0
．． 3wt%, 1f0.001~1.5wt%
, Ti 0.001-0.5 wt%, 80.000
An alloy containing one or more of the above in the range of 1 to 0.1 wt%, the remainder being Al and unavoidable impurities is used as a skin material, and this is an Al having a potential 50 mV or more whiter than the skin material. It is characterized by being clad on at least one side of a core material made of an alloy, and another one of the present invention is a core material made of an alloy, and another one of the present invention is Ni 0.05 to 5 wt%, Z n0
．． 3-1 (hvt%, MSJ0.01-5wt%, C
Contains u0.05~2wt%, and further contains Cr0.001~
0.5 wt%, Zr0.001-0.3 wt%,
T1f0.001 ~ 1.5 wt%, T
i 0.001-0.5wt%, j30.00
An alloy containing one or more types within the range of 01 to O1I wt%, the remainder being Al and unavoidable impurities is used as a skin material, and this is made from an Al alloy having a potential 50 mV or more higher than that of the skin material. A, f which is clad on one side of the core material and further contains Si5wt% or more on the other side.
It is characterized by being clad with a two-alloy brazing filler metal.

[Function] The reason why the Al alloy composition is limited as described above in the present invention is as follows.

Ni addition is Af: +N! This produces fine precipitates in the material, which has the effect of improving the strength of the material both at room temperature and high temperature. This is because the effect is insufficient, and if it exceeds 5 wt%, the ductility of the material may decrease.

Addition of Zn is M! along with Al-Zn system and MLiJ. 1
7Zn, M! 7Zn2 undergoes age hardening due to the generation of the GP zone, which improves its strength at room temperature and when using a heat exchanger.
Furthermore, it has the effect of lowering the potential of the material and giving it a sacrificial effect, and its content is limited to 0.3 to 10 wt%.
This is because if the content is less than 3 wt%, the effect is insufficient, and if it exceeds 10 wt%, intergranular corrosion may occur.

The addition of Mg causes Mg to form a solid solution in the matrix, contributing to an improvement in strength, and together with Zn, MgZn.

Together with tllJZnz and Cu, it ages hardens due to the formation of an Al-Cu-Mg-based GP zone, which contributes to improved strength at room temperature and when using a heat exchanger. However, the content was limited to 0.01-5wt%, which was 0.01wt%.
If it is less than 5 wt%, the effect is insufficient, and if it exceeds 5 wt%, the ductility may decrease. In addition, when used in Nocolok brazing, where flux and Mg react and cause corrosion, it is best to keep the Mg content to 1 wt% or less, especially in the range of 0.02 to 0.7 wt%. is desirable.

Note that Cu is added to the AJ+-CLI system and M! A, f with 7! 0.05wt precipitates the -Cu-My-based GP zone and greatly affects the strength of the material, especially the strength at room temperature, and its content is limited to 0.05-2wt%.
If it is less than 2% by weight, the effect is insufficient, and if it exceeds 2wt%, there is a high risk of melting due to brazing heat and the corrosion resistance of the product is reduced.

The addition of Cr, Zr, l-1t', Ti, and B all produce fine and stable crystal precipitates and have the effect of making the structure of the material uniform, thereby improving the strength and ductility of the material. It is effective in alleviating potential differences around grain boundaries and suppressing stress concentration at grain boundaries due to the precipitation of insoluble compounds.

If each of these elements is less than the lower limit, the effect is insufficient, and if the upper limit is exceeded, coarse intermetallic compounds are formed during casting, reducing the ductility and toughness of the material.

Furthermore, the reason why the core material is an aluminum alloy having a potential 50 mV or more lower than that of the skin material with the above composition and the skin material is clad on at least one side is that the skin material acts as a sacrificial layer for cathodic protection. This is because it protects the core material. Note that the laminated material of the present invention can be clad in multiple layers depending on the purpose.

In this case, the potential difference between the core material and the layer in direct contact is 50 m.
What is necessary in V is necessary. However, the potential difference is 5
The reason why it is set to 0 mV or more is because the effect of the sacrificial layer cannot be reduced if it is less than 50 mV. Note that this sacrificial layer does not need to be the outermost layer of the laminated material, and it is also possible to layer an alloy with a more base potential on the outside. When the above-mentioned skin material is used as a sacrificial layer, 1 to 2
The cladding content is preferably 0%, preferably 3 to 10%.

Next, using an aluminum alloy having a potential 50 mV or more lower than that of the skin material having the above composition as a core material, the skin material can be clad on one side and a brazing material containing 5 wt % or more of 3i on the other side. If 3i is less than 5 wt% in the brazing material referred to herein, the liquidus temperature will be high and sufficient brazing will be difficult. Usually, a brazing filler metal containing 5 to 15 wt% of 3i is used, and the brazing filler metal accounts for 2 to 30% of the total plate thickness, preferably 3 to 30% by weight.
It is best to clad in a range of 15%. In addition, the laminated material of the present invention may be clad in multiple layers as necessary, and in that case, the brazing material and the core material do not need to be in contact with each other;
It may be clad with a brazing material through a layer or a plurality of alloy layers.

〔Example) Next, the present invention will be explained by examples.

JIS 3003003 alloy 05~0.2 wt%Cu
-1.0~1.5 wt% Mrl-Al alloy) is used as the core material, and one side of the core material is clad with an Al alloy plate having the composition shown in Table 1 as a sacrificial layer for 10% of the total plate thickness.
4045045 alloy 0-11, owt%5i-A
A laminated material having a thickness of 1 m and having a cladding of 10% of the total plate thickness using A gold alloy as a brazing material was manufactured by a conventional method.

32rr for tensile test from each of these laminated materials.
A plate with a size of m x 200 mm, a plate with a size of sog x 1oo# for corrosion resistance evaluation, and an inverted T-joint test piece for evaluation of brazeability were cut out. The test piece was then held horizontally as shown in Figure 1.
1050 plate material (Aj!: 99.5 wt% or more) (2) with the laminated material (1) of the present invention abutted at right angles to the upper surface, and the other above-mentioned plate materials were treated with fluoroalumin after pretreatment while remaining in the plate shape. A flux suspension consisting of acid potassium salt was applied and 610'CX5ml was applied in a dry apse gas atmosphere.
The brazing heat was applied under the conditions of n.

In the inverted T-joint test, the condition of the fillet formed at the abutting portion was visually determined, and the results are also listed in Table 1. Next, the 32# x 200# plate materials were processed into JIS No. 5 tensile test pieces, and tensile tests were conducted immediately before brazing, after heating, left for 30 days, and for <90 days.The results are shown in Table 1. Also listed. Also 50rIunx
A 100 g plate material was sealed with a JIS 4045045 alloy surface, and the sacrificial layer surface was subjected to a CASS test for 500 hours, and the depth of pitting corrosion that occurred at that time was measured, and the results are also listed in Table 1.

In addition, JIS 7072072 Alloy I was used as a conventional laminating material.
Similar tests were conducted on laminates clad with S1100 alloy plates as sacrificial layers, and the results are also listed in Table 1.

As is clear from Table 1, the laminated materials Nα1 to NQ of the present invention
No. 8 has good brazing properties, has a consistently high tensile strength with no change over time, and has a maximum pitting depth that is higher than conventional laminated material N (114, N
Much better than Q15.

In contrast, comparative composite material N lacking the essential elements of the sacrificial layer alloy
α9 to Nα11 are inferior in tensile strength and/or maximum pitting depth, and comparative laminated material Nα12, which has a Ni content of 5 wt% or more in the sacrificial layer alloy, has poor plastic workability and cannot be manufactured into a plate material. Moreover, the comparative laminated material NαB whose sacrificial layer alloy has a Cu content of 2 wt % or more melts due to brazing heat.

(Effects of the Invention) As described above, according to the present invention, it is possible to obtain an Al alloy composite material for heat exchanger members having high strength, excellent brazing properties, and corrosion resistance, and other industrially significant effects are achieved.

[Brief explanation of the drawing]

FIG. 1 is a side view showing a brazeability evaluation test of the laminated material of the present invention. 1・・・・・・Laminated material of the present invention

Claims (4)

[Claims] (1) Ni0.05-5wt%, Zn0.3-10wt
%, Mg0.01-5wt%, and further Cr0.0
01-0.5wt%, Zr0.001-0.3wt%,
Hf0.001-1.5wt%, Ti0.001-0.
5wt%, B0.0001 to 0.1wt%, and the remainder is Al and unavoidable impurities.
1. An Al alloy laminated material for a heat exchanger member, characterized in that at least one side of a core material made of an Al alloy having a noble potential of 0 mV or more is clad. (2) Ni0.05-5wt%, Zn0.3-10wt
%, Mg0.01-5wt%, and further Cr0.0
01-0.5wt%, Zr0.001-0.3wt%,
Hf0.001-1.5wt%, Ti0.001-0.
5wt%, BO. 0001 to 0.1wt% of any one or two or more types, and the remainder is Al and unavoidable impurities.
An Al for a heat exchanger member, characterized in that one side of a core material made of an Al alloy having a noble potential of 0 mV or more is clad, and the other side is clad with an Al alloy brazing filler metal containing 5 wt% or more of Si. Alloy laminating material. (3) Ni0.05-5wt%, Zn0.3-10wt
%, Mg0.01-5wt%, Cu0.05-2wt%
Contains Cr0.001~0.5wt%, Zr0
．． 001-0.3wt%, Hf0.001-1.5wt
%, Ti0.001~0.5wt%, B0.0001~
The skin material is an alloy containing one or more of the above within the range of 0.1 wt%, the remainder consisting of Al and unavoidable impurities, and this is made of an Al alloy that has a potential 50 mV or more nobler than the skin material. An Al alloy laminated material for a heat exchanger member, characterized in that a core material is clad on at least one side. (4) Ni0.05-5wt%, Zn0.3-10wt
%, Mg0.01-5wt%, Cu0.05-2wt%
Contains Cr0.001~0.5wt%, Zr0
．． 001-0.3wt%, Hf0.002-1.5wt
%, Ti0.001~0.5wt%, B0.0001~
0. A core material made of an Al alloy containing one or more of these within the range of lwt%, with the remainder being Al and unavoidable impurities as a skin material, and having a potential 50 mV or more nobler than the skin material. An Al alloy composite material for a heat exchanger member, characterized in that one surface of the aluminum alloy is clad, and the other surface is clad with an Al alloy brazing filler metal containing 5 wt% or more of Si.