Aluminum fin alloy and method of making the same

Patent metadata

Field	Value
Publication number	US-9719156-B2
Application number	US-201213708644-A
Country	US
Kind code	B2
Filing date	Dec 7, 2012
Priority date	Dec 16, 2011
Publication date	Aug 1, 2017
Grant date	Aug 1, 2017

Abstract

The present invention relates to an aluminum alloy product for use as a finstock material within brazed heat exchangers and, more particularly, to a finstock material having high strength and conductivity after brazing. The invention is an aluminum alloy finstock comprising the following composition in weight %:

Fe
 0.8-1.25;

Si
 0.8-1.25;

Mn
0.70-1.50;

Cu
0.05-0.50;

Zn
up to 2.5;

other elements less than or equal to 0.05 each and less than or equal to 0.15 in total; and
balance aluminum.

The invention also relates to a method of making the finstock material.

First claim

What is claimed is:

1. An aluminum alloy finstock consisting of the following composition in weight %:

Fe
 0.8-1.25;

Si
 0.8-1.25;

Mn
0.70-1.50;

Cu
0.05-0.50;

Zn
up to 2.5;

and balance aluminum, wherein the aluminum alloy finstock possesses a longitudinal UTS≧140 MPa and a conductivity≧46% IACS after brazing at 600° C., wherein a gauge of the aluminum alloy finstock is <0.07 mm.

2. The aluminum alloy finstock of claim 1 , wherein the Si content is 0.9-1.1 weight %.

3. The aluminum alloy finstock of claim 1 , wherein the Mn content is 0.9-1.1 weight %.

4. The aluminum alloy finstock of claim 1 , wherein the Zn content is 0.25-2.5 weight %.

5. The aluminum alloy finstock of claim 4 , wherein the aluminum alloy finstock possesses a conductivity>48% IACS after brazing.

6. The aluminum alloy finstock of claim 1 , wherein the Fe content is 0.9-1.1 weight %.

7. The aluminum alloy finstock of claim 1 , wherein the Mn content is 0.7-1 weight %.

8. The aluminum alloy finstock of claim 1 , wherein the gauge of the aluminum alloy finstock is <0.06 mm.

9. The aluminum alloy finstock of claim 1 , wherein the gauge of the aluminum alloy finstock is <0.055 mm.

10. The aluminum alloy finstock of claim 1 , wherein an average grain size of the aluminum alloy finstock after brazing is >110 μm.

11. The aluminum alloy finstock of claim 1 , wherein an average grain size of the aluminum alloy finstock after brazing is >240 μm.

12. A method of making aluminum alloy finstock comprising the following steps:
a) continuously casting an aluminum alloy melt consisting of the following composition in weight %:

Fe
 0.9-1.25;

Si
 0.8-1.25;

Mn
 0.7-1.5;

Cu
0.05-0.5;

Zn
up to 2.5;

and balance aluminum;
b) hot rolling the continuously cast sheet;
c) interannealing the hot rolled sheet; and
d) cold rolling the sheet to a foil gauge, wherein the aluminum alloy finstock possesses a longitudinal UTS≧140 MPa and a conductivity≧46% IACS after brazing at 600° C., wherein the foil gauge is <0.07 mm.

13. The method of claim 12 , wherein the continuous casting step a) is a twin roll casting process.

14. The method of claim 12 , wherein the foil gauge is <0.06 mm.

15. The method of claim 12 , wherein the foil gauge is <0.055 mm.

16. An aluminum alloy finstock consisting of the following composition in weight %:

Fe
 0.9-1.25;

Si
 0.8-1.25;

Mn
 0.7-1.5;

Cu
0.05-0.5;

Zn
up to 2.5;

and balance aluminum,
wherein the aluminum alloy finstock is produced by a method comprising casting an aluminum alloy melt comprising the composition of the aluminum alloy finstock by a continuous strip casting process, wherein a gauge of the aluminum alloy finstock is <0.07 mm, and
wherein the continuous strip casting process is twin roll casting with an average cooling rate not exceeding 1500° C./sec or belt and block casting with a maximum average cooling rate of less than 250° C./sec.

17. The aluminum alloy finstock of claim 16 , wherein the continuous strip casting process is the twin roll casting with the average cooling rate greater than 200° C./sec.

18. An aluminum alloy finstock comprising the following composition in weight %:

Fe
 0.8-1.25;

Si
 0.8-1.25;

Mn
 0.7-1.5;

Cu
0.05-0.5;

Zn
up to 2.5;

other elements less than or equal to 0.05 each and less than or equal to 0.15 in total; and balance aluminum,
wherein the content of Fe and Si are approximately equal; and
wherein the aluminum alloy finstock possesses a longitudinal UTS≧140 MPa and a conductivity≧46% IACS after brazing at 600° CU, and wherein a gauge of the aluminum alloy finstock is <0.07 mm.

Assignees

• Novelis Inc

Inventors

• Howells Andrew D
• Gatenby Kevin Michael
• Marois Pierre Henri
• Davisson Thomas L
• Perdriset Fred

Classifications

• C22C21/00 Primary

  Alloys based on aluminium · CPC title

• B22D11/003

  Aluminium alloys · CPC title

• B22D11/0622

  formed by two casting wheels · CPC title

• B21B2003/001

  Aluminium or its alloys · CPC title

• B22D11/1206

  for plastic shaping of strands (rolling mills B21B1/46) · CPC title