COBALT-BASED ALLOY COMPRISING GERMANIUM AND METHOD FOR SOLDERING

• US 20130299562A1
• Filed: 12/06/2011
• Published: 11/14/2013
• Est. Priority Date: 01/14/2011
• Status: Active Grant

• Current Assignee: Siemens AG
• Original Assignee: Siemens AG
• Inventors: Randelzhofer, Peter, Singer, Robert, Piegert, Sabastian
• Granted Patent: US 8,763,885 B2
• Time in Patent Office: Days
• US Class Current: 228/119
• CPC Class Codes: B23K 35/3046 Co as the principal constituent
• CPC Class Codes: C22C 19/07 based on cobalt

Abstract

Cobalt-based solder alloys are proposed. The cobalt-based solder alloys have germanium. The germanium has a higher melting point than nickel-based alloys such that the germanium is used advantageously for repairing or treating components having the nickel-based alloys used at high temperatures. The components are repaired or treated by soldering using the cobalt-based solder alloys.

Claims

1-15. -15. (canceled)

16. A cobalt-based solder alloy, comprising (in % by weight):

7.0% to 9.0% nickel,

17% to 21% chromium,

5.0% to 6.5% tungsten,

2.0% to 4.0% tantalum,

0.1% to 0.3% titanium,

13% to 27% germanium,

optionally 0.3% to 0.7% carbon, and

optionally 0.2% to 0.7% zirconium.

17. The solder alloy as claimed in claim 16, further comprising:

7.5% to 8.5% nickel,

18.0% to 20.5% chromium,

5.1% to 6.1% tungsten,

2.5% to 3.2% tantalum,

0.2% titanium,

14% to 26% germanium,

optionally 0.4% to 0.6% carbon, and

optionally 0.3% to 0.6% zirconium.

18. The solder alloy as claimed in claim 16, further comprising 18% to 22% germanium.

19. The solder alloy as claimed in claim 16, wherein the solder alloy comprises zirconium.

20. The solder alloy as claimed in claim 16, wherein the solder alloy comprises carbon.

21. The solder alloy as claimed in claim 16, wherein the germanium is replaced partially or completely by gallium.

22. The solder alloy as claimed in claim 16, wherein the germanium is replaced at most partially by gallium.

23. The solder alloy as claimed in claim 16, wherein the germanium is replaced at most partially by silicon.

24. The solder alloy as claimed in claim 16, wherein the germanium is replaced at most partially by silicon to an extent of 90%.

25. The solder alloy as claimed in claim 16, wherein the cobalt represents the remainder such that no further alloying elements are present.

26. The solder alloy as claimed in claim 16, wherein the solder alloy comprises no molybdenum except for impurities.

27. The solder alloy as claimed in claim 16, wherein the solder alloy contains no manganese and/or no iron except for impurities.

28. The solder alloy as claimed in claim 16, wherein the solder alloy contains no carbon and/or no zirconium except for impurities.

29. The solder alloy as claimed in claim 16, wherein the solder alloy does not represent a mixture of two or more alloys.

30. The solder alloy as claimed in claim 16, wherein the solder alloy has no admixture of a base alloy with a higher melting point.

31. The solder alloy as claimed in claim 16, wherein the solder alloy contains silicon.

32. The solder alloy as claimed in claim 16, wherein the solder alloy contains at least 0.3% by weight silicon and/or 1.0% by weight gallium.

33. A method for repairing a nickel-based substrate, comprising:

soldering the substrate using a cobalt-based solder alloy as claimed in claim 16.

34. The method as claimed in claim 33, wherein the soldering is carried out at between 1130°

C. and 1270°

C.

35. The method as claimed in claim 33, wherein the solder alloy is used without a further admixture.