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

The present patent has resulted in a material (aluminum alloy fin material, brazing sheet, and heat exchanger) that has a reduced decrease in sheet thickness after heating (less than before), which helps to prevent a clearance between the fin material and other members. This results in higher bondability and a fin material that can be used for brazing with reduced thickness and weight.

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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