Solderable fluid channel for a heat exchanger of aluminum

Patent metadata

Field	Value
Publication number	US-10222145-B2
Application number	US-201113809983-A
Country	US
Kind code	B2
Filing date	Jul 12, 2011
Priority date	Jul 16, 2010
Publication date	Mar 5, 2019
Grant date	Mar 5, 2019

Abstract

The invention relates to a fluid channel for a heat exchanger, comprising a metal sheet, wherein the metal sheet has at least one core region of an aluminum base alloy and at least one structure arranged inside the fluid channel, wherein the structure lies against a surface of the metal sheet and can be soldered to the metal sheet in a flux-free manner by way of a first soldering location in a soldering operation, and wherein a soldering region of the metal sheet and a counterpart lie against one another and can be soldered to one another in the same soldering operation as a second soldering location while wetting with flux, wherein an open path between the two soldering locations exists before the soldering operation.

First claim

The invention claimed is:

1. A fluid channel for a heat exchanger, comprising:
a metal sheet forming a tube having a first surface and a second surface, wherein the metal sheet is bent such that the first surface bounds the fluid channel and the second surface in part faces an environment, wherein the metal sheet comprises at least one core region comprising an aluminum base alloy, wherein the tube has a first flat side and a second flat side;
at least one first structure formed by a 180° bend in the metal sheet projecting from the first flat side toward the second flat side and arranged inside the fluid channel dividing the fluid channel into multiple chambers, wherein a portion of the at least one first structure lies against a flat portion of the first surface of the metal sheet having no projection on the second flat side and is joined to the first surface of the metal sheet by a first solder joint that does not contain a flux material;
a second structure formed by a joining of a first edgefold and a second edgefold, wherein the second structure comprises a soldering region of the second surface of the metal sheet on the first edgefold and a counterpart region of the second surface of the metal sheet on the second edgefold, wherein the soldering region and the counterpart region lie against one another and are joined by a second solder joint containing a flux material,
wherein the counterpart region comprises an at least one unilateral solder plating having the following composition:
7-11% Si,
0-0.8% Fe,
0-1% Cu,
0.03-2.5% Mg,
0-4% Zn,
0-0.2% Ti,
0-0.5% Bi, and
0-0.2% Sr,
wherein a remainder of the composition is Al; and

a capillary gap formed between the soldering region and the counterpart region, wherein the capillary gap comprises a contact surface, wherein at one end the capillary gap is connected to a flushing channel and at another end the capillary gap is connected to the environment, wherein the flushing channel is approximately of triangular shape having two side walls formed the second surface of the metal sheet which converge toward the capillary gap and one side wall formed by the first surface of the metal sheet, wherein the flushing channel permits discharging the flux material from the second solder joint.

2. The fluid channel as claimed in claim 1 ,
wherein a core region of the metal sheet has a magnesium content of at least approximately 0.03%.

3. The fluid channel as claimed in claim 1 , wherein the magnesium content of the at least one unilateral solder plating is between 0.03% and 0.8%.

4. The fluid channel as claimed in claim 1 ,
further comprising turbulators made of an aluminum alloy where each turbulator is inserted into a chamber of the fluid channel.

5. The fluid channel as claimed in claim 4 ,
wherein the aluminum alloy of the turbulator contains no more than 0.7% magnesium or wherein the at least one unilateral solder plating has a magnesium content between 0.03% and 0.8%,
wherein the metal sheet contains magnesium for soldering to the turbulator without flux material.

6. The fluid channel as claimed in claim 4 , wherein the aluminum alloy of the turbulator contains no more than 0.7% magnesium and/or contains an at least one unilateral solder plating having a magnesium content of between 0.03% and 0.8%.

7. The fluid channel as claimed in claim 1 , wherein the fluid channel is in the form of a flat tube having a fold which runs in a longitudinal direction of the tube, wherein the fold is in the form of a soldering region of the metal sheet.

8. The fluid channel as claimed in claim 7 ,
wherein the at least one first structure is in the form of at least one web which is shaped from the metal sheet and lies against the first surface of the metal sheet, forming and forms a multi-chamber flat tube.

9. The fluid channel as claimed in claim 7 , wherein the soldering region of the metal sheet has a fold portion which is soldered areally with wetting by flux material and an adjoining edgefold bent through more than 90°.

10. The fluid channel as claimed in claim 9 , wherein the following equation applies for a length L of the adjoining edgefold and a thickness D of the metal sheet:
L> 2* D;
wherein, for the case of an edgefold bent through 180°, the following equation further applies:
L <( B− 2.5* D ), with a width B of the flat tube.

11. The fluid channel for a heat exchanger as claimed in claim 1 ,
wherein the flushing channel is bounded by the counterpart region and the soldering region,
wherein a width of the flushing channel is greater than that of the capillary gap and is sufficient to permit discharging of flux material.

12. The fluid channel for a heat exchanger according to claim 1 ,
wherein the metal sheet has a core region having the following composition:
0-0.7% Fe,
0.3-1.2% Cu,
0-0.5% Cr,
0-0.3% Ti,
0-1.2% Si,
0-2.0% Mn,
0.1-1.0% Mg,
0-0.2% Zr,
wherein a remainder of the composition is Al.

13. The fluid channel for a heat exchanger according to claim 12 , wherein the metal sheet comprises three layers having the following structure: solder plating/core region/solder plating.

14. The fluid channel for a heat exchanger according to claim 12 , wherein the metal sheet comprises five layers having the following structure: top layer/solder plating/core region/solder plating/top layer.

15. A fluid channel for a heat exchanger, comprising:
a metal sheet having a first surface and a second surface, wherein the metal sheet is bent such that the first surface bounds the fluid channel and the second surface in part faces an environment, wherein the metal sheet comprises at least one core region comprising an aluminum base alloy;
at least one structure formed by a 180° bend in the metal sheet and arranged inside the fluid channel dividing the fluid channel into multiple chambers, wherein a portion of the at least one structure lies against a flat portion of the first surface of the metal sheet and is joined to the first surface of the metal sheet by a first solder joint that does not contain a flux material, wherein a soldering region of the second surface of the metal sheet and a counterpart region of the second surface of the metal sheet lie against one another and are joined by a second solder joint containing a flux material,
wherein the counterpart region comprises an at least one unilateral solder plating having the following composition:
7-11% Si,
0-0.8% Fe,
0-1% Cu,
0.03-2.5% Mg,
0-4% Zn,
0-0.2% Ti,
0-0.5% Bi, and
0-0.2% Sr,
wherein a remainder of the composition is Al,

wherein the metal sheet has a core region having the following composition:
0-0.7% Fe,
0.3-1.2% Cu,
0-0.5% Cr,
0-0.3% Ti,
0-1.2% Si,
0-2.0% Mn,
0.1-1.0% Mg,
0-0.2% Zr,
wherein a remainder of the composition is Al,

wherein the metal sheet comprises three layers having the following structure: solder plating/core region/solder plating; and
a capillary gap formed between the soldering region and the counterpart region, wherein the capillary gap comprises a contact surface, wherein at one end the capillary gap is connected to a flushing channel and at another end the capillary gap is connected to the environment, wherein the flushing channel is approximately of triangular shape having two side walls formed the second surface of the metal sheet which converge toward the capillary gap and one side wall formed by the first surface of the metal sheet, wherein the flushing channel is bounded by the counterpart region and the soldering region, wherein the flushing channel permits discharging the flux material from the seco

Assignees

• Englert Peter
• Gruenenwald Bernd
• Kurz Volker
• Mahle Int Gmbh

Inventors

• Englert Peter
• GRüNENWALD BERND
• Kurz Volker

Classifications

• B23K1/0012

  Brazing of heat exchangers · CPC title

• B21C37/151

  Making tubes with multiple passages · CPC title

• F28F21/084

  from aluminium or aluminium alloys · CPC title

• F28F21/08 Primary

  of metal · CPC title

• F28F2275/06

  by welding · CPC title