Aluminum alloy fin material, aluminum alloy brazing sheet, and heat exchanger

Abstract

An aluminum alloy fin material includes an aluminum alloy containing 1.50 to 5.00 mass % Si with the balance of Al and inevitable impurities, and has the function of being bonded by heating with a single layer. Assuming that in a cross section along the thickness direction of the fin material, the equivalent circle diameter of a Si particle is represented by D, a distance from a surface layer to the center of the Si particle is represented by L, the thickness of the fin material is represented by t, and a length parallel to the surface layer is represented by W, all Si particles that are present in the range of the length W and satisfy D≥L and L+D>0.04 t also satisfy 0≤ΣπD2<0.08 tW. An aluminum alloy brazing sheet includes, as a skin material, the fin material that is clad on a core material including an aluminum alloy. A heat exchanger includes the fin material or the brazing sheet that is used in a fin.

Description

TECHNICAL FIELD[0001]The present disclosure relates to an aluminum alloy fin material, an aluminum alloy brazing sheet, and a heat exchanger.BACKGROUND ART[0002]Conventionally, brazing fins of which the skin materials are clad with Al—Si-based alloys have been commonly used as aluminum alloy fin materials having the function of being bonded to tubes by heating. In such a brazing fin, a skin material is melted and flows in the case of heating and bonding, and therefore, a sheet thickness is decreased according to the melting. Patent Literature 1 discloses a fin materials having the function of being bonded by heating with a single-layer material but does not disclose suppression of a decrease in sheet thickness.[0003]For example, in each of the end edges of many sheet-shaped fins arranged at a predetermined spacing from each other in a fm-and-tube-type heat exchanger, plural notch grooves opened to penetrate the same positions of the sheet-shaped fins are disposed along each of the e...

AI Technical Summary

Benefits of technology

[0021]The aluminum alloy fin material, aluminum alloy brazing sheet, and heat exchanger according to the present disclosure have a small decrease in the sheet thickness of the fin material, the low deterioration of bondability, and the low deterioration of rigidity in bonding and heating. Specifically, since the rate of decrease in sheet thickness after the heating is less than that before the heating for bonding in the fin material, a clearance generated between the fin material and another member at the time of the heating for bonding can be suppressed. As a result, the fin material having high bondability and the brazing sheet using the fin material can be obtained. Since the less decrease in sheet thickness can result in the less deterioration of rigidity after the bonding, the thicknesses of the fin material and the brazing sheet can be reduced, and the weight of the heat exchanger using the fin material and the brazing sheet can be reduced.

Problems solved by technology

Patent Literature 1 discloses a fin materials having the function of being bonded by heating with a single-layer material but does not disclose suppression of a decrease in sheet thickness.

There is a problem that a clearance between a tube surface and a fin surface becomes large when such a heat exchanger is bonded and heated and the sheet thickness of a fin material is reduced at the time of the bonding.

There is a problem that when a decrease in sheet thickness is large, it is impossible to fill the clearance with a melted bonding assistant, and a bonding rate is decreased.

A decrease in sheet thickness due to the heating for bonding results in the deterioration of rigidity due to a decrease in the cross-sectional area of the fin.

There is a problem that, therefore, it is necessary to use a fin material of which the thickness is larger than a fin sheet thickness required after the heating for bonding, resulting in an increase in the cost of the material.

However, a decrease in cladding ratio in the fin material having a small sheet thickness precludes production of the fin material.

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