JP2968290B2 - A ▲ High-strength Al ▲ alloy fin material for heat exchange - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-strength A-alloy fin material for an A-heat exchanger, which has a high strength and can be made thinner.

[Conventional technology]

Conventionally, an A heat exchanger generally used as a radiator of an automobile or an air conditioner is formed by cladding a brazing material of an A-Si alloy on a surface of a core material of an A-Mn alloy, for example. Assembling a tube member made of a sheet and a fin member also made of an A-Mn alloy into a predetermined shape, heating the assembly in a vacuum atmosphere, and brazing the fin member to the tube member. And the fin material has many A
It is also well known that alloys are applied. Among them, the same applicant has previously filed Japanese Patent Application No. 56-105350 (Japanese Patent Application Laid-Open No. 58-6956) with Mn: 0.1-1.5%, Si: 0.1 to 1.5%, Zr: 0.02 to 0.2%, Fe: 0.1 to 1.%, Ni: 0.05 to 0.3%, one or two of the following, with the balance being We have proposed a fin material for an A heat exchanger composed of an A alloy having a composition of A and inevitable impurities (more than% by weight, the following% indicates% by weight).

[Problems to be solved by the invention]

On the other hand, in recent years, demands for speeding up, miniaturization, and weight reduction of various vehicles are severe, and accordingly, there is a tendency that structural members of the A heat exchanger, particularly fin materials, are required to be further reduced in thickness, At present, many fin materials, including the above-mentioned conventional alloy fin materials, cannot satisfy the demand for thinning due to insufficient strength.

[Means for solving the problem]

In view of the above, the inventors conducted research to develop a fin material for A heat exchanger which has high strength and enables thinning, and as a result, the fin material was changed from Fe: 1.1 to 1.5%, Si: 0.35 to 0.51%, Mn: 0.1 to 0.26%, and the remainder is composed of an A alloy having a composition consisting of A and unavoidable impurities. The research results showed that the material could be made thinner.

The present invention has been made based on the above research results, and the reason for limiting the component composition of the A alloy constituting the fin material as described above will be described below.

(A) Si and Mn These components form an A-Mn-Si-based compound that is finely dispersed in the substrate rather than forming a solid solution in the substrate, thereby improving the high-temperature strength of the fin material. Upon heating at the time of brazing, even if the fin material is in a thin state, it has an effect of preventing deformation of the fin material and performing good brazing, and in this case, since these components actively form the above compound, Since the solid solution in the base material is suppressed, the fin material retains high thermal conductivity and low potential, but when the content is less than 0.35% for Si: and less than 0.1% for Mn, respectively, The desired effect is not obtained, while the content is
If Si: 0.51% and Mn: 0.26%, respectively, the solid solution amount of Si and Mn in the base material increases, the thermal conductivity decreases, and the potential increases, and 51.0% (IACS) or more Since the electric conductivity and the potential of -750 mV vs. SCE or less cannot be secured, and the sacrificial anode effect on the tube material is reduced, the contents are respectively set to Si: 0.35 to 0.51%, M
n: 0.1 to 0.26%.

(B) Fe The Fe component mainly has a function of improving the room-temperature strength by forming an A-Fe-based compound which is preferentially bonded to A at the time of melting and casting and forms finely dispersed in the base material. As in the case of Si and Mn in the case of the formation of the A-Mn-Si based compound, since the solid solution of the Fe component is suppressed in the base material, the effect of improving the thermal conductivity and the effect of lowering the potential are maintained. If the content is less than 1.1%, desired effects cannot be obtained in the above-mentioned action, while if the content exceeds 1.5%, the proportion of the Fe component dissolved in the matrix similarly to Si and Mn is large. Thermal conductivity decreases, the potential increases, the A-Fe-based compound coarsens, the high-temperature strength decreases, and the processability also decreases.
1.51.5%.

〔Example〕

Next, the fin material of the present invention will be specifically described with reference to examples.

Each of the A alloy melts having the component compositions shown in Table 1 was prepared and semi-continuously cast into ingots using a water-cooled mold having a plane inner surface dimension of 30 mm x 150 mm. Hot-rolled, and then cold-rolled under the same conditions, with intermediate annealing applied as necessary, and the final cold-rolling rate is set to 30%. Inventive fin materials 1 to 5 and comparative fin material 1
To 6 were each manufactured.

The comparative fin materials 1 to 6 have a component content (marked with * in Table 1) of any of the constituent components of the A alloy constituting the comparative fin materials 1 to 6 is outside the scope of the present invention.

Then, the fin materials 1 to 5 of the present invention and the comparative fin materials 1 to 6 obtained as described above were evaluated for electric conductivity for evaluating thermal conductivity, electric potential for evaluating sacrificial anode effect on tube material, and room temperature strength. In order to evaluate the tensile strength, respectively, and to evaluate the high-temperature strength,
Using a test piece of width: 30 mm × length: 140 mm, With one side of the test piece 35 mm free, under conditions equivalent to brazing conditions, i.e., in a vacuum of 15 ^-5 torr, 60
Heat treatment was performed at 0 ° C. for 5 minutes, and the hanging height at the tip of the protruding portion of the test piece was measured. The results of these measurements are shown in Table 1.

〔The invention's effect〕

From the results shown in Table 1, the fin materials of the present invention 1 to 5
Means that the electrical conductivity is 51.0% (IACS) or more and-
750 mV vs. SCE or lower, and thus exhibiting excellent room temperature and high temperature strength while maintaining excellent thermal conductivity and low potential, as shown in Comparative Fin Materials 1-6. It is clear that if the content of any one of the A alloys constituting the above deviates from the range of the present invention, at least one of the above-mentioned properties becomes inferior.

As described above, the fin material of the present invention has high room temperature and high temperature strength while maintaining excellent thermal conductivity and low potential. Since the fin material is not deformed in the brazing process during the manufacture of the exchanger, good brazing can be performed, and the sacrifice anode effect on the tubing is excellent, so that the tubing is well protected against corrosion and has good heat. Combined with having conductivity, it exhibits excellent performance,
It has industrially useful properties, such as allowing the heat exchanger to be used for a long time.

Claims (1)

(57) [Claims] (1) Fe: 1.1 to 1.5%, Si: 0.35 to 0.51%, Mn: 0.1 to 0.26%, and the balance is composed of an A alloy having a composition of A and unavoidable impurities (at least% by weight). A fin material made of a high-strength A alloy for an A heat exchanger.