JPH0368730A - Manufacture of copper alloy and copper alloy material for radiator plate - Google Patents

Abstract

PURPOSE:To manufacture the Cu alloy material having excellent stress corrosion cracking resistance, strength, formability, solderability, etc., as a radiator plate for joining with a tank made of resin by subjecting a cold rolled sheet of a Cu-Zn-Ni series alloy having specified compsn. of final annealing and furthermore subjecting it to cold rolling at a specified draft. CONSTITUTION:As a radiator plate 7 used for a radiator tank 6 made of resin, a cold rolled sheet having intermediate sheet thickness of a Cu alloy constituted of, by weight, 5 to 30% Zn, 0.1 to 10% Ni and the balance Cu or a Cu alloy contg., as the elements for improving strength, furthermore contg. 0.001 to 2.0% of one or more kinds among Al, Fe, Pb, As, Sb, B, Co, Cr, Mn, Te, In, Ti, Zr, Hf, Be, Mg, Ag, Cd and Ge is subjected to final annealing and is furthermore subjected to final cold rolling at 3 to 20% draft. The Cu alloy sheet material as a radiator plate having <=15mum grain size and having excellent various characteristics can be manufactured.

Description

[Detailed Description of the Invention] [Industrial Application Fields] The present invention provides excellent stress corrosion cracking resistance, strength, formability, and solderability for radiator plates, especially for radiator plates for joining with resin tanks. , relates to a copper alloy that has adhesive properties with resin.

[Prior Art] Conventionally, a radiator plate is fixed to a radiator tube and fixed to the radiator tongue. That is, in Fig. 1, l is a brass tank;
2 is a radiator plate, 4 is a radiator tube, and 5 is a radiator fin. Soldering 3 is used to fix these, and strength, moldability, and solderability are required. On the other hand, in recent years, resin tanks 6 have been used from the viewpoint of corrosion resistance, as shown in Fig. 2, and radiator plates 7
It is no longer possible to solder the resin tank 6, and a caulking method has been adopted. 8 in FIG. 2 is a sealing material.

In this case, unlike conventional radiator plates, the radiator plate material is required to have the following properties because bending and caulking are required.

(1) Good bendability; (2) Good caulking. In other words, it has a high yield strength, (3) no stress corrosion cracking occurs at the bent part, (4) high strength, (5) good press formability, and (8) good solderability. There is (adhesion with radiator tube).

[Problems to be Solved by the Invention] Despite these various required characteristics, the brass that has been conventionally used is susceptible to stress corrosion cracking.

In addition, the Zn content was increased to 20% to improve stress corrosion cracking resistance.
% red copper is being considered, but the strength and yield strength are lowered, good caulking cannot be obtained, and it is not sufficient to meet the recent strict requirements for stress corrosion cracking resistance. It's coming.

The present invention was made in view of this point, and the present invention was made using conventional brass,
The aim is to improve the drawbacks of red copper and provide an excellent copper alloy for use in radiator plates.

[Means for Solving the Problems] The present invention uses 5 to 30% by weight of Zn, N i 0.1=lO
% by weight, with the balance consisting of Cu and unavoidable impurities; and 5-30% by weight of Zn, 0.1-10% by weight of Ni, and further includes Al, Fe5Pb.

As, 5bSB, Co, Cr, Mn5Te.

I n ST i 1Z r SHf SB e 1M
A copper alloy for radiator plates, characterized in that it contains 0.001 to 2% by weight of one or more of the group consisting of g SA g NCd5Ge, and the balance consists of Cu and unavoidable impurities. It is desirable that the crystal grain size is 15 μm or less.

Furthermore, the present invention relates to a method for manufacturing a copper alloy material for a radiator plate, characterized in that an alloy having the above composition is cold rolled to an intermediate thickness, and after final annealing, cold rolling is performed at a workability of 3 to 20%. .

Next, the reasons for limiting the alloy components constituting the present invention will be explained below.

The reason why the Zn content is set to 5 to 30% by weight is that if the Zn content is less than 5% by weight, the strength will be low and the price will be high. Furthermore, if the Zn content exceeds 30% by weight, the stress corrosion cracking property increases significantly. More ideally, the Zn content is preferably 20% by weight or less.

The reason why the Ni content is set to o, t-to weight percent is that the addition of Ni is effective in improving stress corrosion cracking resistance and yield strength, but
．． This is because if it is less than 1% by weight, there is no effect, and if it exceeds 10% by weight, processability will deteriorate.

Furthermore, AI, Fe, Pb, ASSSbx B%Cos
Cr, Mn, Te, In5TiSZr, Hf5Be, M
The reason why one or more elements from the group consisting of gSAg5CdSGe is set at 0.001 to 2.0% by weight is that these elements are effective in improving strength without inhibiting stress corrosion cracking resistance. This is because if the content is less than 0.001% by weight, there is no effect, and if it exceeds 2.0% by weight, processability will deteriorate.

Furthermore, the reason why the crystal grain size of the alloy of the present invention is limited to 15 μm or less is that if the crystal grain size exceeds 15 μm, the stress corrosion cracking susceptibility increases, so it is desirable that the crystal grain size is 15 μm or less.

Furthermore, the reason why the alloy of the present invention is cold rolled with a working degree of 3 to 20% after final annealing is that cold rolling improves the solderability of the alloy of the present invention. However, if the degree of working is less than 3%, no improvement in soldering properties will be observed, and if it exceeds 20%, the mechanical strength will become too high and the formability of caulking will deteriorate.

[Example 7] An ingot made by melting and casting an alloy having the composition shown in Table 1 in the air or an inert atmosphere was hot-rolled, and then cold-rolled and annealed repeatedly to form a plate having a thickness of 0.81 mm. This cold-rolled material was annealed at 500 to 800°C for 15 minutes to adjust the grain size, and the sample was used as a sample. In addition, a plate with an intermediate thickness was prepared by cold rolling, annealed at 500 to 800°C for 15 minutes to adjust the grain size, and then subjected to a skin bath if necessary to obtain a plate with a thickness of 0.11111. did. As an evaluation of such samples, the strength, yield strength, grain size, stress corrosion test, and soldering resistance of the materials are shown in Table 1.

For the stress corrosion cracking test, a JIS conical cup test tool type 17 cylindrical flat bottom punch was used, and the drawing ratio was 2.
A cup with a pH of 0 was made, and the cup was exposed to an ammonia atmosphere with a pH of 0 made of sodium hydroxide and ammonium chloride, and the time until cracking started was measured.

For soldering, a molten metal is made by heating 5N20%-Pb80% solder to 320℃ in a cylindrical crucible with a diameter of 80 mm and a depth of 80 mm.
Sample at 5txts/sea (width 1 with surface cleaned)
hsq length 50III shape) was immersed in the solder bath, the time required for the buoyant force received by the sample from the solder bath and the force drawn into the solder bath to reach equilibrium was measured and evaluated.

As is clear from Table 1, the alloy of the present invention obtained satisfactory results in all properties, but comparative alloy No. 13
Since the Zn content is low, the strength is not sufficient. Furthermore, alloy No. 14.17 has poor stress corrosion cracking resistance due to its low Ni content.

In addition, comparative alloy No. I5 has poor stress corrosion cracking resistance because it has too much Zn content. Furthermore, comparative alloy No. 16
Because the crystal grain size is too large, the stress corrosion cracking resistance is poorer than that of invention alloy No. 2. Inventive alloy No. 5.7 has improved solderability by performing skin bath cold rolling on Inventive alloy No. 4.6.

[Effects of the Invention] As detailed above, the present invention can provide a material that has excellent strength, stress corrosion cracking resistance, and solderability, and is optimal as a copper alloy for radiator plates.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a conventional method of joining a brass tank and a radiator plate, and FIG. 2 is a sectional view showing a method of joining a resin tank and a radiator plate. l...Brass tank, 2...Radiator plate, 3...Soldering, 4...Radiator tube, 5...Radiator fin, 6...Resin tank, 7...Radiator plate , 8... Sealing material.

Claims (4)

[Claims] (1) A copper alloy for radiator plates containing 5 to 30% by weight of Zn and 0.1 to 10% by weight of Ni, with the balance consisting of Cu and unavoidable impurities. (2) Contains 5-30% by weight of Zn, 0.1-10% by weight of Ni, and further contains Al, Fe, Pb, As, Sb, B, Co
, Cr, Mn, Te, In, Ti, Zr, Hf, Be,
A copper alloy for a radiator plate, characterized in that it contains 0.001 to 2.0% by weight of one or more of the group consisting of Mg, Ag, Cd, and Ge, with the remainder being Cu and inevitable impurities. (3) The copper alloy for radiator plates according to claims (1) and (2), characterized in that the crystal grain size is 15 μm or less. (4) Contains 5-30% by weight of Zn, 0.1-10% by weight of Ni, or further contains Al, Fe, Pb, As, Sb
, B, Co, Cr, Mn, Te, In, Ti, Zr, H
Contains 0.001 to 2.0% by weight of one or more from the group consisting of f, Be, Mg, Ag, Cd, Ge, the balance being C
Manufacture of a copper alloy material for a radiator plate, characterized by cold rolling an alloy material consisting of u and inevitable impurities to an intermediate plate thickness, and further cold rolling with a workability of 3 to 20% after final annealing. Law.