ALUMINIUM BRAZING SHEET MATERIAL FOR FLUXLESS BRAZING

• US 20130306714A1
• Filed: 01/19/2012
• Published: 11/21/2013
• Est. Priority Date: 01/31/2011
• Status: Active Grant

• Current Assignee: Novelis Koblenz GmbH
• Original Assignee: Aleris Rolled Products Germany GmbH
• Inventors: Wittebrood, Adrianus Jacobus
• Granted Patent: US 8,763,880 B2
• Time in Patent Office: Days
• US Class Current: 228/219
• CPC Class Codes: B23K 1/0012 Brazing heat exchangers
• CPC Class Codes: B23K 1/19 taking account of the properties of the materials to be soldered
• CPC Class Codes: B23K 35/0233 Sheets, foils B23K35/0244 takes precedence
• CPC Class Codes: B23K 35/0238 layered
• CPC Class Codes: B23K 35/286 Al as the principal constituent
• CPC Class Codes: B23K 35/288 with Sn or Zn
• CPC Class Codes: B23K 35/38 Selection of media, e.g. special atmospheres for surrounding the working area
• CPC Class Codes: B32B 15/016 all layers being formed of aluminium or aluminium alloys
• CPC Class Codes: C22C 1/02 by melting C22C1/1036 takes precedence
• CPC Class Codes: C22C 1/06 with the use of special agents for refining or deoxidising
• CPC Class Codes: C22C 21/02 with silicon as the next major constituent
• CPC Class Codes: C22C 21/04 Modified aluminium-silicon alloys
• CPC Class Codes: C22C 21/06 with magnesium as the next major constituent
• CPC Class Codes: C22C 21/08 with silicon
• CPC Class Codes: C22C 21/10 with zinc as the next major constituent
• CPC Class Codes: C22F 1/043 of alloys with silicon as the next major constituent
• CPC Class Codes: C22F 1/047 of alloys with magnesium as the next major constituent
• CPC Class Codes: F28F 21/089 Coatings, claddings or bonding layers made from metals or metal alloys F28F19/06 takes precedence
• CPC Class Codes: Y10T 428/12222 Shaped configuration for melting [e.g., package, etc.]

Abstract

A brazing sheet material including a core alloy layer bonded on at least one side with an aluminium brazing clad layer or layers forming a filler material of a 4000-series aluminium alloy. The core layer is made from an aluminium alloy having (in wt. %): Mg 1.0 to 3.0, Mn 0 to 1.8, Cu 0 to 0.8, Si 0 to 0.7, Fe 0 to 0.7, optionally one or more elements selected from the group (Zr, Cr, Hf, T), Zn 0 to 0.5, impurities and aluminium. The filler material forms a 4000-series aluminium alloy further including one or more wetting elements selected from Bi 0.03-0.5, Pb 0.03-0.5, Sb 0.03- 0.5, Li 0.03-0.5, Se 0.03-0.5, Y 0.03-0.05, Th 0.03-0.05, wherein the sum of these elements being 0.5% or less.

Claims

1. A brazing sheet material comprising of a core alloy layer bonded on at least one side with an aluminium brazing clad layer or layers forming a filler material of a 4000-series aluminium alloy, wherein the core layer is made from an aluminium alloy comprising, in wt. %:

2. A brazing sheet material according to claim 1, wherein the core alloy has a Mg content of 2.0% to 3.0%.

3. A brazing sheet material according to claim 1, wherein the core alloy has a Mg content of 1.0 to 2.8%.

4. A brazing sheet material according to claim 1, wherein the core alloy has a Si content of 0.1% to 0.7%.

5. A brazing sheet material according to claim 1, wherein the core alloy has a Mg content of 2.3% to 3.0%.

6. A brazing sheet material according to claim 1, wherein the core alloy has a Si content of 0.1% to 0.6%.

7. A brazing sheet material according to claim 1, wherein the core alloy is on one side bonded with the filler material, and bonded on the other side with a waterside liner material.

8. A brazing sheet material according to claim 1, wherein the filler material has a Si content of 9 to 12%.

9. A brazing sheet material according to claim 1, wherein the core alloy is on one side bonded with the filler material, and bonded on the other side with an aluminium brazing clad layer of an AA4000-series aluminium alloy.

10. A brazing sheet material according to claim 1, wherein the brazing sheet material is devoid of a diffusion barrier formed by an interliner layer positioned between the core alloy layer and the brazing clad layer.

11. A method of manufacturing an article, in particular a heat exchanger, joined by brazing or an assembly of brazed components, comprising the steps of:

(a) providing of the components to be brazed together of which at least one is made from an aluminium brazing sheet material according to claim 1;

(b) assembling the components into an assembly;

(c) brazing the assembly without applying brazing flux onto the assembly of components, and brazing the whole assembly in an inert gas atmosphere at a brazing temperature;

(d) cooling of the brazed assembly.

12. A brazing sheet material according to claim 1, wherein the core alloy has a Cu content of 0 to 0.3%.

13. A brazing sheet material according to claim 1, wherein the core alloy has a Cu content of 0 to 0.1%.

14. A brazing sheet material according to claim 1, wherein the core alloy has a Fe content of 0.07% to 0.7%.

15. A brazing sheet material according to claim 1, wherein the core alloy has a Fe content of 0.07% to 0.4%.

16. A brazing sheet material according to claim 1, wherein the core alloy has a Mn content in a range of 0.5% to 1.8%.

17. A brazing sheet material according to claim 1, wherein the core alloy has a Mn content in a range of 0.5% to 1.0%.

18. A brazing sheet material according to claim 1, wherein the filler material has a Bi content in the range of 0.12% to 0.35%.

19. A brazing sheet material according to claim 1, wherein the filler material has a Mg content in the range of 0.15% to 0.3%.

20. A brazing sheet material according to claim 1, wherein the filler has an excess Mg-content of 0.07% or less with respect to stoichiometric composition of Bi2Mg3.

21. A brazing sheet material according to claim 1, wherein the filler material has a Cu content of 0 to 0.05%.

22. A brazing sheet material according to claim 1, wherein the core layer is made from an aluminium alloy comprising, in wt. %:

23. A brazing sheet material according to claim 1, wherein the core has 0.06 to 0.4% Hf.

24. A brazing sheet material according to claim 1, wherein the core has 0.2 to 0.3% Ti.