Nickel-based brazing foil and process for brazing

• US 20090110955A1
• Filed: 10/14/2008
• Published: 04/30/2009
• Est. Priority Date: 10/15/2007
• Status: Active Grant

• Current Assignee: Vacuumschmelze GmbH & Company KG (Vectra Corp.)
• Original Assignee: Vacuumschmelze GmbH & Company KG (Vectra Corp.)
• Inventors: Hartmann, Thomas, Nuetzel, Dieter
• Granted Patent: US 9,757,810 B2
• Time in Patent Office: Days
• US Class Current: 428/684
• 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 35/3033 Ni as the principal constituent
• CPC Class Codes: B23K 35/304 with Cr as the next major constituent
• CPC Class Codes: C22C 1/11 Making amorphous alloys
• CPC Class Codes: C22C 19/05 with chromium
• CPC Class Codes: C22C 19/058 without Mo and W
• CPC Class Codes: C22C 45/04 with nickel or cobalt as the major constituent
• CPC Class Codes: C22F 1/002 by rapid cooling or quenching; cooling agents used therefor
• CPC Class Codes: C22F 1/10 of nickel or cobalt or alloys based thereon
• CPC Class Codes: C22F 3/00 Changing the physical structure of non-ferrous metals or alloys by special physical methods, e.g. treatment with neutrons
• CPC Class Codes: F02M 26/29 Constructional details of the coolers, e.g. pipes, plates, ribs, insulation or materials
• CPC Class Codes: F28F 21/083 from stainless steel
• 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 428/12944 Ni-base component
• CPC Class Codes: Y10T 428/12972 Containing 0.01-1.7% carbon [i.e., steel]

Abstract

Disclosed is an amorphous, ductile brazing foil with a composition consisting essentially of Ni_restCr_aB_bP_cSi_d with 2 atomic percent ≦a≦30 atomic percent; 0.5 atomic percent ≦b≦14 atomic percent; 2 atomic percent ≦c≦20 atomic percent; 0 atomic percent ≦d≦14 atomic percent; incidental impurities ≦0.5 atomic percent; rest Ni, where c>b>c/15 and 10 atomic percent ≦b+c+d≦25 atomic percent. Also disclosed is amorphous, ductile Ni-based brazing foil having a composition consisting essentially of Ni_restCr_aB_bP_cSi_dC_eX_fY_g wherein a, b, c, d, e, f, and g are numbers such that 2 atomic percent ≦a≦30 atomic percent; 0.5 atomic percent ≦b≦14 atomic percent; 2 atomic percent ≦c≦20 atomic percent; 0 atomic percent ≦d≦14 atomic percent; 0 atomic percent ≦e≦5 atomic percent; 0 atomic percent ≦f≦5 atomic percent; 0 atomic percent ≦g≦20 atomic percent; wherein incidental impurities are present, if at all, in amounts ≦0.5 atomic percent; wherein rest indicates that the balance of the composition is Ni; wherein c>b>c/15; wherein 10 atomic percent ≦b+c+d≦25 atomic percent, wherein X is one or more of the elements Mo, Nb, Ta, W and Cu; and wherein Y is one or both of the elements Fe and Co. Also disclosed are methods for making and using these brazing foils, and brazed objects produced therefrom.

Claims

1. An amorphous, ductile Ni-based brazing foil having a composition consisting essentially of

Ni_restCr_aB_bP_cSi_d

wherein a, b, c, and d are numbers such that 2 atomic percent ≦

a≦

30 atomic percent;

0.5 atomic percent ≦

b≦

14 atomic percent;

2 atomic percent ≦

c≦

20 atomic percent;

0 atomic percent ≦

d≦

14 atomic percent;

wherein incidental impurities are present, if at all, in amounts ≦

0.5 atomic percent;

wherein rest indicates that the balance of the composition is Ni;

wherein c>

b>

c/15; and

wherein 10 atomic percent ≦

b+c+d≦

25 atomic percent.

3. The amorphous, ductile brazing foil in accordance with claim 1 wherein the Cr content a is such that 16 atomic percent ≦

a≦

30 atomic percent.

4. The amorphous, ductile brazing foil in accordance with claim 1, wherein the B content b is such that 1 atomic percent ≦

b≦

8 atomic percent.

5. The amorphous, ductile brazing foil in accordance with claim 1, wherein the P content c is such that 5 atomic percent ≦

c≦

18 atomic percent.

6. The amorphous, ductile brazing foil in accordance with claim 1, wherein the Si content d is such that d=0 atomic percent.

7. The amorphous, ductile brazing foil in accordance with claim 1, wherein the Si content d is such that 0 atomic percent ≦

d≦

14 atomic percent.

11. The amorphous, ductile brazing foil in accordance with claim 1, wherein the brazing foil is at least 50% amorphous.

12. The amorphous, ductile brazing foil in accordance with claim 1, wherein the brazing foil is at least 80% amorphous.

13. The amorphous, ductile brazing foil in accordance claim 1, wherein the foil has a thickness D of 15 μ

m ≦

D≦

75 μ

m.

14. The amorphous, ductile brazing foil in accordance with claim 1, wherein the foil has a width B of 0.5 mm ≦

B≦

300 mm.

15. The amorphous, ductile brazing foil in accordance with claim 13, wherein the width B is 30 mm ≦

B≦

150 mm.

16. The amorphous, ductile brazing foil in accordance with claim 1, wherein the foil varies in thickness from a mean thickness of the foil in a variation of less than 25% over a length of 200 m.

17. The amorphous, ductile brazing foil in accordance with claim 1, wherein the foil varies in thickness from a mean thickness of the foil in a variation of less than 20% over a length of 100 m.

18. The amorphous, ductile brazing foil in accordance with claim 1, wherein the foil variesin thickness from a mean thickness of the foil in a variation of less than 10% over a length of 5000 m.

19. The amorphous, ductile brazing foil in accordance with claim 1, wherein the foil varies in thickness from a mean thickness of the foil in a variation of less than 15 μ

m over a length of 100 m.

20. The amorphous, ductile brazing foil in accordance with claim 1, wherein the foil has a liquidus temperature of less than 1100°

C.

21. The amorphous, ductile brazing foil in accordance with claim 20, wherein the liquidus temperature of the foil is less than 1080°

C.

22. The amorphous, ductile brazing foil in accordance with claim 21, wherein the liquidus temperature of the foil is less than 1050°

C.

23. A brazed object having a first part joined to a second part by a solder seam produced by heating the brazing foil of claim 1.

24. The brazed object in accordance with claim 23, wherein both the first part and the second part are made of a stainless steel.

25. The brazed object in accordance with claim 23, wherein the solder seam has a thickness that is >

15 μ

m.

26. The brazed object in accordance with claim 23, wherein the brazed object is a heat exchanger.

27. The brazed object of claim 26, wherein the heat exchanger is an exhaust gas recirculation cooler or an oil cooler.

28. The brazed object of claim 24, wherein the brazed object is a heat exchanger.

29. The brazed object of claim 25, wherein the brazed object is a heat exchanger.

32. A process for joining by fusion two or more parts comprising:

inserting of a brazing foil in accordance with claim 1 between two or more parts to be joined, wherein the parts to be joined have a higher melting temperature than that the brazing foil to form a solder joint;

heating the solder joint to a temperature above the liquidus temperature of the brazing foil to form a heated solder joint;

cooling the heated solder joint, thereby forming a brazed joint between the parts to be joined.

34. The process in accordance with claim 32, wherein the heating of the solder joint to a temperature above the liquidus temperature of the brazing foil is carried out in inert gas.

35. The process in accordance with claim 32, wherein the heating of the solder joint to a temperature above the liquidus temperature of the brazing foil is carried out in a continuous furnace.

2. An amorphous, ductile Ni-based brazing foil having a composition consisting essentially of

Ni_restCr_aB_bP_cSi_dC_eX_fY_g

wherein a, b, c, d, e, f, and g are numbers such that 2 atomic percent ≦

a≦

30 atomic percent;

0.5 atomic percent ≦

b≦

14 atomic percent;

2 atomic percent ≦

c≦

20 atomic percent;

0 atomic percent ≦

d≦

14 atomic percent;

0 atomic percent ≦

e≦

5 atomic percent;

0 atomic percent ≦

f≦

5 atomic percent;

0 atomic percent ≦

g≦

20 atomic percent;

wherein incidental impurities are present, if at all, in amounts ≦

0.5 atomic percent;

wherein rest indicates that the balance of the composition is Ni;

wherein c>

b>

c/15;

wherein 10 atomic percent ≦

b+c+d≦

25 atomic percent, wherein X is one or more of the elements Mo, Nb, Ta, W and Cu; and

wherein Y is one or both of the elements Fe and Co.

8. The amorphous, ductile brazing foil in accordance with claim 2, wherein the X content f is such that 0 atomic percent ≦

f≦

3 atomic percent.

9. The amorphous, ductile brazing foil in accordance with claim 2, wherein the Y content g is such that 0 atomic percent ≦

g≦

5 atomic percent.

10. The amorphous, ductile brazing foil in accordance with claim 9, wherein the Y content g is 0 atomic percent ≦

g≦

1 atomic percent.

33. A process for joining by fusion two or more parts comprising:

inserting of a brazing foil in accordance with claim 2 between two or more parts to be joined, wherein the parts to be joined have a higher melting temperature than that the brazing foil to form a solder joint;

heating the solder joint to a temperature above the liquidus temperature of the brazing foil to form a heated solder joint;

cooling the heated solder joint, thereby forming a brazed joint between the parts to be joined.

30. A process for producing an amorphous ductile brazing foil comprising:

providing a molten mass consisting essentially of Ni_restCr_aB_bP_cSi_d wherein a, b, c, and d are numbers such that 2 atomic percent ≦

a≦

30 atomic percent;

0.5 atomic percent ≦

b≦

14 atomic percent;

2 atomic percent ≦

c≦

20 atomic percent;

0 atomic percent ≦

d≦

14 atomic percent;

wherein incidental impurities are present, if at all, in amounts ≦

0.5 atomic percent;

wherein rest indicates that the balance of the molten mass is Ni, wherein c>

b>

c/15 and wherein 10 atomic percent ≦

b+c+d≦

25 atomic percent,

rapidly solidifying the molten mass on a moving cooling surface with a cooling speed of more than approximately 10⁵°

C./sec to produce an amorphous, ductile brazing foil.

31. A process for producing an amorphous ductile brazing foil comprising:

providing a molten mass consisting essentially of Ni_restCr_aB_bP_cSi_dC_eX_fY_g wherein a, b, c, d, e, f, and g are numbers such that 2 atomic percent ≦

a≦

30 atomic percent;

0.5 atomic percent ≦

b≦

14 atomic percent;

2 atomic percent ≦

c≦

20 atomic percent;

0 atomic percent ≦

d≦

14 atomic percent;

0 atomic percent ≦

e≦

5 atomic percent;

0 atomic percent ≦

f≦

5 atomic percent;

0 atomic percent ≦

g≦

20 atomic percent, wherein incidental impurities are present, if at all, in amounts ≦

0.5 atomic percent;

wherein rest indicates that the balance of the molten mass is Ni;

wherein c>

b>

c/15 and 10 atomic percent ≦

b+c+d≦

25 atomic percent;

wherein X is one or more of the elements Mo, Nb, Ta, W and Cu; and

wherein Y is one or both of the elements Fe and Co,

rapidly solidifying the molten mass on a moving cooling surface with a cooling speed of more than approximately 10⁵°

C./sec to produce an amorphous ductile brazing foil.