JP2943482B2 - Al-Heat Exchanger Working Fluid Channel Forming Structural Member with Skin Material Exhibiting Sacrificial Anode Effect for Long Term - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an Al heat exchanger in which a skin material exhibits a sacrificial anode effect for a remarkably long period of time, thereby extending the service life of the Al heat exchanger. The present invention relates to a working fluid passage forming structural member.

[0002]

2. Description of the Related Art In general, a radiator for an automobile, an oil cooler, an Al heat exchanger such as an intercooler, etc., are all structural members for forming a working fluid passage such as a water pipe, a header plate, a header pipe, etc., all made of Al alloy. It is well known that the fins are manufactured by assembling fins or the like by vacuum brazing or flux brazing.

Further, the working fluid passage forming structural member of the Al heat exchanger is, for example, by weight% (hereinafter,% indicates weight%), Mn: 0.5 to 1.5%, Cu: 0.3 ~
0.7%, and if necessary, Zr: 0.
05 to 0.3%, Cr: 0.05 to 0.3%, Ti:
0.05 to 0.3%, one or more of which are contained, and the remaining In: 0. 00
A composite material obtained by cladding a sacrificial anode skin material of an Al alloy having a composition of 5 to 0.06%, with the balance being Al and unavoidable impurities, and a side opposite to the skin material of the composite material It is also known that the brazing sheet is formed of a brazing sheet by cladding a brazing material (JISZ3263) of an Al-Si alloy or an Al-Si-Mg alloy.

[0004]

However, in the above-mentioned conventional working fluid passage forming structural member, the skin material constituting the same is made electrochemically sufficiently lower by the In contained as an alloy component than the core material. The sacrificial anode effect is exhibited, and the core material is well protected, but the corrosion rate of the skin material is fast and the corrosion progresses locally, so the core material is exposed in a relatively short time. And pitting corrosion occurs, and as a result, it is difficult to expect a sacrificial anode effect of the skin material over a long period of time.

[0005]

Means for Solving the Problems Accordingly, the present inventors have
From the above-mentioned viewpoint, focusing on the above-mentioned conventional working fluid passage forming structural member, while making the corrosion of the skin material gradual, suppressing the occurrence of pitting, and exhibiting a sacrificial anode effect over a long period of time. As a result of studying the above, in the above-mentioned conventional working fluid passage forming structural member, the sacrificial anode skin material constituting the same was made of In: 0.005 to 0.06%, S:
i: 0.05-0.3%, Mg: 0.05-
0.3%, Zn: 0.05-0.3%, one of them
Or two or more, and if necessary, Mn:
0.2 to 1.5%, the balance being made of an Al alloy having a composition of Al and unavoidable impurities, the Si contained as an alloy component impairs the sacrificial anode effect of In. In addition, the corrosion rate becomes slow and the corrosion becomes extremely slow. Research results show that the material exhibits a sacrificial anode effect over a long period of time, and that the inclusion of the Mn component can further reduce the corrosion rate in the presence of the Si component. It was.

The present invention has been made on the basis of the above research results, wherein Mn: 0.5-1.5%,
Cu: 0.3-0.7%, Zr: 0.05-0.3%, Cr: 0.05-
0.3%, Ti: 0.05 to 0.3%, one or two or more of which, the remainder being a working fluid passage of an Al alloy core material having a composition composed of Al and unavoidable impurities. On the side, In: 0.005 to 0.06%, Si: 0.05
~ 0.3%, Mg: 0.05-0.3%,
Zn: one or two of 0.05 to 0.3%
Species, and if necessary, Mn: 0.2 to
A composite material obtained by cladding a sacrificial anode skin material of an Al alloy having a composition of 1.5%, with the balance being Al and unavoidable impurities, and further, on the opposite side of the skin material of the composite material, It has a feature in a working fluid passage forming structural member of an Al heat exchanger composed of a brazing sheet formed by cladding a brazing material (JISZ3263) of an Al-Si alloy or an Al-Si-Mg alloy. Also.

Next, the reason why the component composition of the Al alloy constituting the core material and the skin material in the working fluid passage forming structural member of the present invention is limited as described above will be described.

A. Core material (a) Mn The Mn component has the effect of forming an Al-Mn-based intermetallic compound dispersed and distributed in the base material to improve the strength. If the content is less than 0.5%, the desired strength improvement is obtained. No effect can be obtained, and on the other hand, if the content exceeds 1.5%, the workability is reduced.
%.

(B) Cu The Cu component forms a solid solution with the base material to improve the strength, and is made electrochemically noble to increase the potential difference with the skin material, thereby ensuring the sacrificial anode effect of the skin material. However, if the content is less than 0.3%, the desired effect cannot be obtained, whereas if the content exceeds 0.7%, the corrosion resistance decreases. Therefore, the content was determined to be 0.3 to 0.7%.

(C) Zr, Cr, and Ti These components have an effect of forming various intermetallic compounds to improve the strength, and thus are contained as necessary. : Less than 0.05%, C
If r: less than 0.05% and Ti: less than 0.05%, the desired strength-improving effect cannot be obtained, while the contents are Zr: 0.3%, Cr: 0.3%, and Ti, respectively. :
Even if the content exceeds 0.3%, no further effect of improving the strength can be obtained.
3%, Cr: 0.05 to 0.3%, and Ti: 0.0
It was determined to be 5 to 0.3%.

B. Skin material (a) In The In component has the effect of making the skin material electrochemically lower than the core material as described above, thereby exhibiting the sacrificial anode effect. If the content is less than 0.005%, the desired effect cannot be obtained, while if the content exceeds 0.06%, the self-corrosion rate sharply increases. ~ 0.06%

(B) Si In the Si component, the corrosion rate of the skin material is suppressed without impairing the sacrificial anode effect of In as described above, so that the skin material can exhibit the sacrificial anode effect for a remarkably long period. However, if the content is less than 0.05%, the desired effect cannot be obtained, while the content is 0.3%.
%, The potential difference with respect to the core material becomes small and the sacrificial anode effect decreases, so the content was set to 0.05 to 0.3%.

(C) Mg and Zn As described above, these components have the effect of changing the corrosion form to a general corrosion type, which significantly suppresses the occurrence of pitting corrosion. If any of them is less than 0.05%, the desired effect cannot be obtained in the above-mentioned action, and if any of them exceeds 0.3%, the progress of the corrosion rate is accelerated. : 0.05
０．３0.3%, Zn: 0.05-0.3%. (D) Mn Since the Mn component has an effect of further suppressing the corrosion rate of the skin material in the coexistence with Si, it is contained as necessary. When the content exceeds 1.5%, on the other hand, when the content exceeds 1.5%, the potential difference between the skin material and the core material becomes small similarly to Si, and the sacrificial anode effect on the core material cannot be sufficiently exhibited. Therefore, the content was determined to be 0.2 to 1.5%.

[0014]

Next, the working fluid passage forming structural member of the present invention will be described in detail with reference to embodiments. Al alloys A1 to A12 for core material and Al alloys B1 to B for skin material having the component compositions shown in Tables 1 and 2, respectively, by a normal melting casting method.
12, and it was melted brazing material for Al alloys C1, C2, and the ingot was cast into a water-cooled mold, this ingot, 570-60
A homogenization treatment of holding at a predetermined temperature within a range of 0 ° C. for 12 hours and then hot rolling are performed to obtain an Al alloy for a core material of 9.3.
6 mm, the Al alloy for the cladding material and the Al alloy for the brazing material having a thickness of 1.2 mm were overlapped in the combinations shown in Tables 3 and 4, clad by hot rolling, and subsequently cold rolled. To form a composite material having a thickness of 0.3 mm, and from the composite material, a tubular material having a diameter of 10 mm, in which the working fluid passage side (inner side) is made of a skin material, is formed by welding to form a structural member 1 of the present invention. ~
12 and conventional structural members 1 to 12 were manufactured, respectively.

[0015]

[Table 1]

[0016]

[Table 2]

[0017]

[Table 3]

[0018]

[Table 4]

Next, the various structural members obtained as a result were subjected to a brazing condition in vacuum at a temperature of 880K.
, After heating for 5 minutes after cooling, tap water containing 1 ppm of Cu ⁺⁺ ion as a working fluid (temperature: 31
5K) was passed for 15 days at a flow rate of 25 l / min, and the maximum pitting depth and corrosion loss of the skin material were measured. The measurement results are shown in Tables 3 and 4.

[0020]

According to the results shown in Tables 3 and 4, all of the structural members 1 to 12 of the present invention show much slower corrosion progress of the skin material than the conventional structural members 1 to 12, and the pitting corrosion resistance. It is clear that this is excellent.

As described above, the working fluid passage forming structural member of the present invention has a very slow progress of corrosion of the skin material, and the skin material has excellent pitting corrosion resistance. A can be demonstrated
(1) It has industrially useful characteristics such as a large portion that contributes to prolonging the service life of the heat exchanger.

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoichi Wakasa 5-24-15 Minamidai, Nakano-ku, Tokyo Calsonic Co., Ltd. (56) References JP-A-4-198446 (JP, A) JP-A-4 -36433 (JP, A) JP-A-2-54735 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) B32B 15/01 C22C 21/00 F28F 19/06 F28F 21/08

Claims (8)

(57) [Claims] 1. Mn: 0.5 to 1.5%, Cu: 0.3 to 0.7% by weight
%, And the remainder is made of Al alloy core material having a composition consisting of Al and unavoidable impurities, on the working fluid passage side of the core material, In: 0.005 to 0.06%, Si: 0.05 to
0.3%, Mg: 0.05-0.3%, Zn: 0.05-0.3
%, And the remainder is a composite material clad with a sacrificial anode skin material of an Al alloy having a composition consisting of Al and unavoidable impurities. An Al heat exchanger working fluid passage forming structural member that exhibits a sacrificial anode effect for a long time. 2. In% by weight, Mn: 0.5-1.5%, Cu: 0.3-0.7.
%, Zr: 0.05 to 0.3%, Cr: 0.05 to 0.3%
%, Ti: 0.05 to 0.3%, and at least one of two or more of them, and the remainder has a composition of Al and unavoidable impurities. In: 0.005 to 0.06%, Si: 0.05 to
0.3%, Mg: 0.05-0.3%, Zn: 0.05-0.
A sacrificial anode skin material of an Al alloy having a composition comprising Al and unavoidable impurities, and a cladding material comprising a clad composite material. Is an Al heat exchanger working fluid passage forming structural member exhibiting a sacrificial anode effect for a long time. 3. Mn: 0.5 to 1.5%, Cu: 0.3 to 0.7% by weight
%, And the remainder is made of Al alloy core material having a composition consisting of Al and unavoidable impurities, on the working fluid passage side of the core material, In: 0.005 to 0.06%, Si: 0.05 to
0.3%, Mg: 0.05-0.3%, Zn: 0.05-0.3
% Or more, and Mn: 0.2 to 1.5%, and the remainder is clad with a sacrificial anode skin material of an Al alloy having a composition of Al and inevitable impurities. A structural member for forming a working fluid passage in an Al heat exchanger in which a skin material exhibits a sacrificial anode effect for a long period of time, characterized by being constituted by a material. 4. Mn: 0.5-1.5%, Cu: 0.3-0.7% by weight
%, Zr: 0.05 to 0.3%, Cr: 0.05 to 0.3%
%, Ti: 0.05 to 0.3%, and at least one of two or more of them, and the remainder has a composition of Al and unavoidable impurities. In: 0.005 to 0.06%, Si: 0.05 to
0.3%, Mg: 0.05-0.3%, Zn: 0.05-0.
3%, one or two of them, and Mn: 0.2 to 1.2%, and the rest is clad with a sacrificial anode skin material of an Al alloy having a composition consisting of Al and inevitable impurities. A structural member for forming a working fluid passage in an Al heat exchanger, in which a skin material exhibits a sacrificial anode effect for a long time, characterized by being composed of a composite material. 5. Mn: 0.5-1.5%, Cu: 0.3-0.7% by weight
%, And the remainder is made of Al alloy core material having a composition consisting of Al and unavoidable impurities, on the working fluid passage side of the core material, In: 0.005 to 0.06%, Si: 0.05 to
0.3%, Mg: 0.05-0.3%, Zn: 0.05-0.
And a sacrificial anode skin material of an Al alloy having a composition consisting of Al and unavoidable impurities, on the opposite side of the core material from the skin material. An Al heat exchanger working fluid passage formation structure in which a skin material exhibits a sacrificial anode effect for a long time, characterized in that the skin material is made of a composite material clad with a brazing material of an Si-based alloy or an Al-Si-Mg-based alloy. Element. 6. Mn: 0.5 to 1.5%, Cu: 0.3 to 0.7% by weight
%, Zr: 0.05 to 0.3%, Cr: 0.05 to 0.3%
%, Ti: 0.05 to 0.3%, and the balance: Al: 0.005 to 0.06%, on the working fluid passage side of an Al alloy core material having a composition of Al and inevitable impurities. , Si: 0.05-
0.3%, Mg: 0.05-0.3%, Zn: 0.05-0.
3%, one or two of which are Al
A sacrificial anode skin material of an Al alloy having a composition consisting of unavoidable impurities and Al-Si on the opposite side of the core material from the skin material.
Heat exchanger working fluid passage forming member in which a skin material exhibits a sacrificial anode effect for a long time, characterized in that the skin material is constituted by a composite material clad with a brazing material of an Al-Si-Mg-based alloy. . 7. Mn: 0.5 to 1.5%, Cu: 0.3 to 0.7% by weight
%, And the remainder is made of Al alloy core material having a composition consisting of Al and unavoidable impurities, on the working fluid passage side of the core material, In: 0.005 to 0.06%, Si: 0.05 to
0.3%, Mg: 0.05-0.3%, Zn: 0.05-0.
The sacrificial anode skin material of an Al alloy containing 1% or 2% of Mn and 0.2 to 1.5% of Mn and having a balance of Al and unavoidable impurities, A cladding material characterized by being composed of a composite material clad with an Al-Si-based alloy or an Al-Si-Mg-based alloy brazing material on the side opposite to the cladding material, exhibits a sacrificial anode effect for a long time. Al heat exchanger working fluid passage forming structural member. 8. Mn: 0.5 to 1.5%, Cu: 0.3 to 0.7% by weight
%, Zr: 0.05 to 0.3%, Cr: 0.05 to 0.3%
%, Ti: 0.05 to 0.3%, and at least one of two or more of them, and the remainder has a composition of Al and unavoidable impurities. In: 0.005 to 0.06%, Si: 0.05 to
0.3%, Mg: 0.05-0.3%, Zn: 0.05-0.
The sacrificial anode skin material of an Al alloy containing one or two of Mn: 0.2 to 1.5% of Mn and 0.2% to 1.5% of Mn, and having the balance of Al and unavoidable impurities. A skin material characterized by comprising a composite material in which a brazing material of an Al-Si alloy or an Al-Si-Mg alloy is clad on the opposite side of the material from the above-mentioned skin material, for a long period of time, the sacrificial anode effect A structural member for forming a working fluid passage in an Al heat exchanger that exhibits