JPS63293136A - Aluminum alloy and aluminum alloy clad material for heat exchanger member - Google Patents

Abstract

PURPOSE:To obtain the titled Al alloy which shows high strength, excellent brazability and corrosion resistance by incorporating specific ratios of Mg, Si, Fe, Cu and Ni to the alloy and furthermore incorporating one or more kinds from either or both groups between the one of Mn, Cr, Zr, etc., and the other of Zn, In and Sn thereto. CONSTITUTION:The Al alloy for an exchanger member contg., by weight, 0.01-1% Mg, 0.01-1.5% Si, 0.01-1.0% Fe, 0.05-2% Cu and 0.6-5% Ni and furthermore contg. one or more kinds of elements from either or both groups between the one of 0.01-2% Mn, 0.001-0.5% Cr, 0.001-0.5% Zr, 0.001-1.5% Hf, 0.001-0.5% Ti and 0.0001-0.1% B and the other of 0.5-5% Zn, 0.005-0.5% In and 0.005-0.5% Sn is provided. Said Al alloy has good brazability and has excellent strength after brazing. The Al alloy clad material for a heat exchanger member in which said Al alloy is formed to the core and in which the Al alloy wax material contg. >=5wt.% Si and clad on either face or both faces thereof has the excellent characteristics as well equal to said Al alloy.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an aluminum alloy for heat exchanger components manufactured by brazing and a composite material using the alloy as a core material, and particularly relates to an aluminum alloy with excellent strength. It is something.

[Conventional technology]

Conventional heat exchangers, especially automotive heat exchangers such as radiators, heaters, oil coolers, evaporators for air conditioners, condensers, etc., are mostly made of Al alloys, which are molded into the desired shape and then assembled and joined by brazing. There is. The materials for these heat exchangers include Al shown in Table 1.
Or there is an Al alloy.

Examples of when these Al or Al alloys are used alone include extruded multi-hole tubes for air conditioner heat exchangers, fins for laminated type evaporators and oil coolers, and piping for all-Ai type radiators. Alternatively, when an Al alloy is used as a laminating material, a plating sheet is used in which the aluminum alloy brazing material shown in Table 2 is used as the skin material and the Al or Al alloy core material shown in Table 1 is clad on one or both sides.

Examples of the use of the above plating sheets include fin materials for air conditioner heat exchangers, sheet materials for laminated type evaporators and oil coolers, radiator tubes, headers, and tank materials. In order to improve the corrosion resistance inside the parts through which the cooling water or cooling liquid flows, a sacrificial anode layer with a lower potential than the core material is provided on the surface of the plating sheet that comes into contact with the cooling water or cooling liquid to prevent the occurrence of through-pitting corrosion. Other materials are also used.

Al alloys are also used as fin materials for heat exchangers in home and commercial air conditioners.

[Problem to be solved by the invention] Recently, the weight of such heat exchangers has been reduced.

In order to reduce costs, there is an increasing demand for thinner components, and in order to achieve this, materials with higher strength are required, and various alloys are being developed. However, there are approximately 600 parts for heat exchangers, especially parts manufactured by brazing.
The strength during brazing heated to ℃ and the strength after brazing are both high, and if 7lux is used during brazing, there is no reaction with flux, and corrosion resistance is also required after brazing. Since it is necessary to have all of the various performances such as

[Means for solving problems]

In view of this, as a result of various studies, the present invention has developed aluminum alloys and aluminum alloy composite materials for heat exchanger members that have good brazing properties and excellent strength after brazing.

That is, the aluminum alloy of the present invention has M = j 0.01 to 1
wt%, 3i 0.01-1.5 wt%, Fe
0.01-1.0wt%, cuo, os ~2wt%
, Nio, 6 to 5 wt%, and further Mn0.0
1-2wt%, cro, 001-0.5wt%, Z
ro, 001~0.5 Wj%, Hf0.001~
1.5 wt%, T! 0.001~0.5wt
%, 80.0001~0.1 wt% and Zn0.5~
5wt%, In0.005~0.5wt%, S
It is characterized in that any of n0.005 to 0.5 wt% contains one or more elements from one or both groups, and the remainder consists of Al and inevitable impurities.

In addition, one of the aluminum alloy laminated materials of the present invention uses the above-mentioned aluminum alloy as a core material, and has three layers on one or both sides of the core material.
It is characterized by being clad with an aluminum alloy brazing filler metal containing 15 wt% or more.

Furthermore, another one of the aluminum alloy laminated materials of the present invention is characterized in that the above-mentioned aluminum alloy is used as a core material, and one or both sides of the core material is clad with an aluminum alloy having a potential 50 mV or more more base than the core material. It is.

[For production]

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

The addition of Mg dissolves in the matrix and forms fine precipitates of MgzSi together with Si, contributing to the improvement of strength, and the Mg-containing matrix is limited to 0.01 to 1 wt% to less than 0.01 wt%. In this case, sufficient strength cannot be obtained by 1q,
This is because if it exceeds 1 wt%, brazing properties will be significantly inhibited, and in extreme cases, brazing will become impossible.More preferably, 0%
．． A range of 0.02 to 0.6 wt% is good, and in the case of brazing using flux, addition in a range of 0.02 to 0.3 wt% is desirable.

Addition of Sl produces fine precipitates of Mg2Si together with Mg, and when Mn is added, further Al-1vl
The Si content is limited to 0.01 to 1.5 wt% because sufficient strength cannot be obtained with less than 0.01 wt%. ．．
This is because if it exceeds 5 wt%, there is a high risk of melting during brazing heating.

The addition of Fe improves the strength of the material, especially the high-temperature strength, and the reason why the Fe content m is limited to 0.01 to 1.0 wt% is because sufficient strength cannot be obtained with less than 0.01 vt%.
．． If it exceeds 0wt%, it is a gross A! ! This is because -Fe-8i-based or Ai-Fe-xr-based intermetallic compounds are generated and the strength is reduced.

Addition of Cu is AJ! -Cu type and Al-Cu-Mg type 0. P, contributes to improving the strength of the material, especially at room temperature, by precipitating zones, and Cu-containing M is added in an amount of 0.05 to 2wt.
% because if it is less than 0.05 wt %, the above effect will not be sufficient, and if it exceeds 2 wt %, there will be a high risk of melting during brazing heating and the corrosion resistance of the product will be reduced.

The addition of Ni produces fine precipitates of A, esNi, which improves the room temperature and high temperature strength of the material, and also improves the corrosion resistance and fatigue strength.
% because these effects are not sufficient if it is less than 0.6 wt%, and if it exceeds 5 wt%, the ductility of the material is reduced.

Furthermore, Mn0.01~2wt%, Cr0.001~0
．． 5wt%, Zr0. ool ~0.5 wt%,
Hf0.001-1.5 wt%, T i 0.0
01~0.5 wt%, 80.0001~O5i wt
% and Zn0.5-5wt%, In0.005-0.
5 wt%, S no, 005 to 0.5 wt%, one or more elements from either or both groups are added to the first group, that is, Mn, Cr.
, Zr, Hf, Ti, and B all have the effect of producing fine and stable crystallized substances and precipitates and making the structure of the material uniform, and as a result, contribute to improving the strength of the material, especially the high-temperature strength and ductility. The reason why the content of each of these is limited as above is that if the content exceeds the above limit, coarse intermetallic compounds will be generated during casting during material production, reducing the ductility and toughness of the material. This is because no effect can be obtained.

It should be noted that these elements are effective even when added alone, but often have even better effects when added in combination.

However, these elements make the structure uniform and make it finer, so when such an alloy is used for fin materials, etc., if the structure becomes too fine, it will cause problems in areas that come into contact with the filler metal during brazing. 3i in the material is abnormally diffused into the material, resulting in buckling deformation of the material.

Therefore, when the present invention material is used in a member in which Si diffusion is a problem, the amount of these elements added should be kept to the minimum necessary.

In addition, the second group, ie, zn, In, and sn, all have the effect of making the potential of the material base, so they improve the pitting corrosion resistance when the present invention material is used as a part that requires a sacrificial effect. The reason why the content of each is limited as above is because if the amount exceeds this amount, this effect will be saturated and there is a risk of further reducing the ductility of the material.
This is because the effect is not sufficient below the lower limit. Note that these elements may be added singly or in combination of two or more.

For these first element group and second element group, one or more elements selected from either or both element groups should be added depending on the site used.

Next, one of the Al alloy composite materials according to the present invention uses the above-mentioned Al alloy as a core material, and one or both sides of the core material is clad with a brazing material containing 315 wt% or more.
The reason why the content is limited to 5 wt% or more is because if it is less than 5 wt%, the liquidus temperature will be high and the brazing material will not melt sufficiently, making brazing difficult. For this reason, normal brazing filler metal is 5 to 15
Those containing wt% Si are used, and it is also good to add small amounts of Be, Si, Mg, etc. for the purpose of improving brazing properties. The brazing material is preferably clad on one or both sides of the core material in an amount of 3 to 30%, more preferably 5 to 15%, of the total thickness. In addition, such a composite material may be clad in multiple layers as necessary, but in that case, the alloy of the present invention and the brazing material do not need to be in contact with each other, and there may be one or more layers of the alloy between them. It may be clad through layers.

Furthermore, one of the features of the Al alloy laminated material according to the present invention is that the above-mentioned Al alloy is used as a core material, and one or both sides of the aluminum alloy have 50% of the core material.
A, which has a base potential of 0 mV or more, is used to clad a single-layer alloy, but the potential of the Al alloy is made base because the Al alloy acts as a sacrificial layer in cathodic protection and protects the core material, The reason why the potential is set to 50 mV or more is because a sufficient effect cannot be obtained if the potential is less than this.

Note that this sacrificial layer is preferably clad in a range of 1 to 20%, more preferably 3 to 20% of the total thickness.

In addition, when cladding such laminated materials in multiple layers, the core material of the alloy of the present invention and the sacrificial layer do not need to be in direct contact with each other, and the sacrificial layer is 50 m away from the other core material with which it is directly in contact.
It suffices if it has a potential that is more base than V.

The above-mentioned alloys and composite materials of the present invention can be flux brazed,
It can be used as a material for any brazing method such as inert atmosphere brazing and vacuum brazing. Furthermore, these alloys and composite materials can be manufactured by conventional methods.

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

Example (1) After melting an Al alloy having the composition shown in Table 3, it was continuously cast, and the ingot was hot rolled, then cold rolled and annealed to a thickness of 1! M
4 plates were manufactured. A tensile test piece was processed from the plate material, heated at a temperature of 610° C. for 5 minutes under conditions assuming brazing, and then subjected to a tensile test. The results are also listed in Table 3.

Furthermore, as a brazeability test, as shown in Figure 1, a plating sheet was applied to the surface of the plate material as shown in Table 2.
5% of the flux consisting of potassium fluoroaluminate salt after pretreatment using an inverted Tll1 hand specimen against which 12 PCs were abutted! ! ! After applying the cloudy liquid and drying it, heat is added to the brazing in an N2 gas atmosphere to form a fillet at the abutting part.The results are marked with a circle if a good fillet is formed, and if a fillet is not formed or defective. Those with uniform fillets are also marked with an X in Table 3. Also, as a conventional alloy, JIS 3003. JIS 3004 and J
A similar test was conducted on IS 6061 and the results are also listed in Table 3.

As is clear from Table 3, all of the alloys of the present invention have a tensile strength of 20.4 Ky f /- or more, which is superior to conventional alloys, and also has good brazing properties. On the other hand, M9-containing mother is 't
Comparative alloy Nα8 containing more than CU has excellent tensile strength but poor brazing properties, whereas comparative alloy Nα7 containing no CU
．． All comparative alloys Nα9 containing no N+ have inferior tensile strength. In addition, conventional JIS 3003 alloy has good brazing properties but low tensile strength,
It can be seen that the 004 alloy and the JIS 6061 alloy are inferior in both brazeability and tensile strength.

Example (2) Using an ingot of the alloy Nα3 of the present invention shown in Table 3, this plate was used as a core material, and as shown in Table 4, a JIS 4045 alloy plate shown in Table 1 was used as a brazing material on one side. 10 plate thickness
A laminated material having a thickness of 6i or 6o was manufactured by a conventional method, and the other side was clad with a JIS 7072 alloy to a thickness of 10% of the total plate thickness as a sacrificial layer skin material.

After cutting out a board of 32s x 200m from the laminated material J
It was processed into an IS No. 5 tensile test piece and subjected to a tensile test, and the results are shown in Table 4. Also, from the above laminated material, 50
After cutting out the board of aX100#Im, JIS 404
5 alloy surface was sealed, and in order to evaluate the corrosion resistance from the JIS 7072 alloy surface, a 500 hour CASS test was conducted to measure the depth of pitting corrosion, and the results are shown in Table 4.

After pretreatment using an inverted T-joint test piece in which the above-mentioned composite material was pressed against the surface of the JIS 1050 alloy plate material shown in Table 1 as shown in Figure 2, a suspension of flux consisting of potassium fluoroaluminate salt was applied. After coating and drying, brazing heat was applied at 600℃ for 5 minutes in an N2 gas atmosphere, and the brazing properties were evaluated based on the shape of the fillet.The results are shown in Table 4.For comparison, conventional alloy JIS 3003 alloy as a core material, one side is clad with JIS 4045 alloy as a brazing material with a thickness of 10% of the total plate thickness, and the other side is JIS 7
Thickness 1.072 alloy is used as a sacrificial skin material and is clad with a thickness of 10% of the total plate thickness. Orm laminated material was manufactured using a conventional method, and the same tests as above were conducted, and the results were summarized in the 4th section.
Also listed in the table.

Note that the potentials in Table 4 are based on the core material of the above laminated material and JIS 7.
The values are shown for the 072 alloy skin material measured at 25° C. in a 5% NaCl aqueous solution using a saturated calomel electrode as a reference.

As is clear from Table 4, the laminated materials of the present invention are particularly superior in strength and corrosion resistance compared to the comparative materials.

(Effects of the Invention) As described above, according to the present invention, a heat exchanger member having high strength, excellent brazing properties, and corrosion resistance can be obtained.

[Brief explanation of drawings]

Figure 1 is a side view showing the brazeability test of the alloy of the present invention, Figure 2
The figure is a side view showing a brazeability test of the laminated material of the present invention. 1...JIS BAl2PC plating sheet 2... Alloy of the present invention 3... Laminated material of the present invention 4...JIS 1050 Alloy plate material Figure 1
Figure 2

Claims (3)

[Claims] (1) Mg0.01-1wt%, Si0.01-1.
5wt%, Fe0.01-1.0wt%, Cu0.05
~2wt%, Ni0.6~5wt%, and further Mn
0.01-2wt%, Cr0.001-0.5wt%,
Zr0.001-0.5wt%, Hf0.001-1.
5wt%, Ti0.001-0.5wt%, B0.00
01-0.1wt%, Zn0.5-5wt%, In0.
005~0.5wt%, Sn0.005~0.5wt%
An aluminum alloy for heat exchanger members, characterized in that it contains one or more elements from either one or both groups, and the remainder consists of Al and unavoidable impurities. (2) Mg0.01-1wt%, Si0.01-1.
5wt%, Fe0.01-1.0wt%, Cu0.05
~2wt%, Ni0.6~5wt%, and further Mn
0.01-2wt%, Cr0.001-0.5wt%,
Zr0.001-0.5wt%, Hf0.001-1.
5wt%, Ti0.001-0.5wt%, B0.00
01-0.1wt%, Zn0.5-5wt%, In0.
005~0.5wt%, Sn0.005~0.5wt%
An aluminum alloy containing one or more elements from either or both groups, the remainder being Al and unavoidable impurities as a core material, and containing 5wt% or more of Si on one or both sides of the core material. An aluminum alloy laminated material for heat exchanger parts, characterized by cladding with brazing filler metal. (3) Mg0.01-1wt%, Si0.01-1.
5wt%, Fe0.01-1.0wt%, Cu0.05
~2wt%, Ni0.6~5wt%, and further Mn
0.01-2wt%, Cr0.001-0.5wt%,
Zr0.001-0.5wt%, Hf0.001-1.
5wt%, Ti0.001-0.5wt%, B0.00
01-0.1wt%, Zn0.5-5wt%, In0.
005~0.5wt%, Sn0.005~0.5wt%
The core material is an aluminum alloy containing one or more elements from either one or both groups, the remainder being Al and unavoidable impurities, and one or both sides of the core material has a voltage of 50 mV or more than the core material. An aluminum alloy laminated material for a heat exchanger member, characterized in that it is clad with an aluminum alloy having a base potential.