Heat exchanger, and fin material for said heat exchanger

Patent metadata

Field	Value
Publication number	US-10408550-B2
Application number	US-201414895204-A
Country	US
Kind code	B2
Filing date	Jun 2, 2014
Priority date	Jun 2, 2013
Publication date	Sep 10, 2019
Grant date	Sep 10, 2019

Abstract

There is provided a heat exchanger and a fin material for the heat exchanger that can suppress occurrence of hollow corrosion in a fin and hold cooling performance for a long period of time under a high corrosion environment. The heat exchanger includes an aluminum tube through which a working fluid circulates and an aluminum fin which is bonded to the tube. The fin has a region B around a grain boundary, and a region A around the region B. In the region B, 5.0×104 pieces/mm2 less of Al—Fe—Mn—Si based intermetallic compound, each of which has equivalent circle diameters of 0.1 to 2.5 μm, are present. In the region A, 5.0×104 pieces/mm2 to 1.0×107 pieces/mm2 of Al—Fe—Mn—Si based intermetallic compound, each of which has equivalent circle diameters of 0.1 to 2.5 μm, are present.

First claim

The invention claimed is:

1. A heat exchanger comprising:
an aluminum tube through which a working fluid circulates; and
an aluminum fin which is bonded to the tube,
wherein the aluminum fin has a region B around a grain boundary, and a region A around the region B, in the region B, 5.0×10 4 pieces/mm 2 less of Al—Fe—Mn—Si based intermetallic compound, each of which has equivalent circle diameters of 0.1 to 2.5 μm, are present, and in the region A, 5.0×10 4 pieces/mm 2 to 1.0×10 7 pieces/mm 2 of Al—Fe—Mn—Si based intermetallic compound, each of which has equivalent circle diameters of 0.1 to 2.5 μm, are present,
an average area of the region B per a length of the grain boundary is set as s μm and satisfies 2<s<40,
an area occupancy ratio of the region A on a surface of the fin is equal to or more than 60%,
the aluminum tube comprises a tube material comprising a 3000-series or 1000-series extruded perforated tube and having a Si content less than 1.0 mass %,
the aluminum fin comprises a fin material having a heat bonding ability in a single layer, wherein the fin material comprises an aluminum alloy containing Si:1.0 mass % to 5.0 mass %, Fe:0.1 mass % to 2.0 mass %, Mn:0.1 mass % to 2.0 mass % with balance being Al and inevitable impurities, 250 pieces/mm 2 to 7×10 4 pieces/mm 2 of Si based intermetallic compound, each of which has equivalent circle diameters of 0.5 to 5 μm, are present, and 10 pieces/mm 2 to 1000 pieces/mm 2 of Al—Fe—Mn—Si based intermetallic compound, each of which has equivalent circle diameters of greater than 5 μm, are present, and
an Al—Si eutectic structure is not on the surface of the aluminum tube other than a fillet at a bonding portion of the aluminum fin and the aluminum tube.

2. The heat exchanger according to claim 1 , wherein
when a grain size of an Al matrix in an L-LT cross-section of the fin is set as L μm, and a grain size of an Al matrix in an L-ST cross-section of the fin is set as T μm , L≥100 and L/T≥2.

3. The heat exchanger according to claim 1 ,
wherein the aluminum alloy further contains one or more selected from among Mg:2.0 mass % or less, Cu:1.5 mass % or less, Zn:6.0 mass % or less, Ti:0.3 mass % or less, V:0.3 mass % or less, Zr:0.3 mass % or less, Cr:0.3 mass % or less and Ni:2.0 mass % or less.

4. The heat exchanger according to claim 1 , wherein the fin comprises a fin material having a heat bonding ability in a single layer,
wherein the fin material comprises an aluminum alloy containing Si:1.0 mass % to 5.0 mass % and Fe:0.01 mass % to 2.0 mass % with balance being Al and inevitable impurities including Mn,
wherein 250 pieces/mm 2 to 7×10 5 pieces/mm 2 of Si based intermetallic compound, each of which has equivalent circle diameters of 0.5 to 5 μm, are present, and 100 pieces/mm 2 to 7×10 5 pieces/mm 2 of Al—Fe—Mn—Si based intermetallic compound, each of which has equivalent circle diameters of 0.5 to 5 μm, are present.

5. The heat exchanger according to claim 4 ,
wherein the aluminum alloy further contains one or more selected from among Mn:2.0 mass % or less, Mg:2.0 mass % or less, Cu:1.5 mass % or less, Zn:6.0 mass % or less, Ti:0.3 mass % or less, V:0.3 mass % or less, Zr:0.3 mass % or less, Cr:0.3 mass % or less and 2.0 mass % or less of Ni.

6. The heat exchanger according to claim 1 , wherein the fin comprises a fin material having a heat bonding ability in a single layer,
wherein the fin material comprises an aluminum alloy containing Si:1.0 mass % to 5.0 mass % and Fe:0.01 mass % to 2.0 mass % with balance being Al and inevitable impurities including Mn,
wherein 200 pieces/mm 2 less of Si based intermetallic compound, each of which has equivalent circle diameters of 5.0 to 10 μm, are present, and 10 pieces/mm 2 to 1×10 4 pieces/μm 3 of Al—Fe—Mn—Si based intermetallic compound, each of which has equivalent circle diameters of 0.01 to 0.5 μm, are present.

7. The heat exchanger according to claim 6 , wherein
the aluminum alloy further contains one or more selected from among Mn:0.05 mass % to 2.0 mass %, Mg:0.05 mass % to 2.0 mass %, Cu:0.05 mass % to 1.5 mass %, Zn:6.0 mass % or less, Ti:0.3 mass % or less, V:0.3 mass % or less, Zr:0.3 mass % or less, Cr:0.3 mass % or less and Ni:2.0 mass % or less.

8. The heat exchanger according to claim 1 , wherein
a natural potential of the fin is equal to or greater than −910 mV, and
the natural potential of the fin is nobler than a natural potential of the fillet by 0 mV to 200 mV.

9. The heat exchanger according to claim 8 , wherein
relationships between natural potentials at the fin (Fin), a surface of the tube (TS), a core of the tube (TB), and the fillet (Fillet) satisfy the following expressions:
TS-Fillet≤200 mV  (1),

Fillet≥−950 mV  (2),

TB-TS≥100 mV  (3), and

TS≥−950 mV  (4).

10. The heat exchanger according to claim 3 , wherein the aluminum alloy further contains 0.3% or less of Sn, or 0.3% or less of In.

Assignees

• Uacj Corp

Inventors

• Murase Takashi
• Kitawaki Kotaro
• KUROSAKI Tomohito
• Ninomiya Junji

Classifications

• F28F19/06

  of metal · CPC title

• F28F1/12

  the means being only outside the tubular element · CPC title

• C22F1/043

  of alloys with silicon as the next major constituent · CPC title

• C22C21/02

  with silicon as the next major constituent · CPC title

• B22D11/0622

  formed by two casting wheels · CPC title