Preheating temperature during welding

• US 20090134133A1
• Filed: 10/07/2008
• Published: 05/28/2009
• Est. Priority Date: 10/08/2007
• Status: Abandoned Application

• Current Assignee: Siemens AG
• Original Assignee: Siemens AG
• Inventors: Mokadem, Selim
• Application Number:
  US12/287,182
• Publication Number:
  US 20090134133A1
• Time in Patent Office: Days
• US Class Current: 219/121.640
• CPC Class Codes: B23K 10/02 Plasma welding
• CPC Class Codes: B23K 2101/001 Turbines
• CPC Class Codes: B23K 2103/50 Inorganic material, e.g. metals, not provided for in B23K2103/02 – B23K2103/26
• CPC Class Codes: B23K 26/32 taking account of the properties of the material involved
• CPC Class Codes: B23K 26/60 Preliminary treatment
• CPC Class Codes: B23K 9/0026 specially adapted for particular articles or work
• CPC Class Codes: B23K 9/235 Preliminary treatment
• CPC Class Codes: B23P 6/007 using only additive methods, e.g. build-up welding
• CPC Class Codes: F01D 5/005 Repairing methods or devices
• CPC Class Codes: F05D 2230/232 by welding
• CPC Class Codes: F05D 2230/40 Heat treatment
• CPC Class Codes: F05D 2300/607 Monocrystallinity
• CPC Class Codes: Y02T 50/60 Efficient propulsion technologies, e.g. for aircraft

Abstract

The invention relates to a method of welding locally a surface of a Ni base, especially a single crystal superalloy substrate using a laser beam while preheating the substrate to an optimized temperature for the purpose of repairing cracks. Welding repair of single crystal super alloys often leads to two main types of defects: cracks and spurious grains. Both defects can be avoided using an optimized preheating temperature set to higher than 500° C.

Claims

1-23. -23. (canceled)

24. A method for welding a component, comprising:

preheating the component at a preheating temperature that is higher than 500°

C. and lower than 600°

C.

25. The method as claimed in claim 24, wherein the preheating temperature is higher than 510°

C.

26. The method as claimed in claim 24, wherein the preheating temperature is higher than 520°

C.

27. The method as claimed in claim 24, wherein the preheating temperature is below 550°

C.

28. The method as claimed in claim 24, wherein the component is made of a material selected from the group consisting of:

a nickel based superalloy, a directionally solidified columnar grained, and a single crystal superalloy.

29. The method as claimed in claim 24, wherein the component is welded by a laser beam.

30. The method as claimed in claim 24, wherein the component is welded by a plasma.

31. The method as claimed in claim 24, wherein the component is preheated locally in an area to be welded.

32. The method as claimed in claim 24, wherein a material is added to an area to be welded.

33. The method as claimed in claim 24, wherein no material is added to an area to be welded.

34. The method as claimed in claim 24, wherein the preheating temperature is maintained during the welding.

35. The method as claimed in claim 24, wherein the component is preheated by an induction system.

36. The method as claimed in claim 24, wherein the component is preheated by an infrared lamp.

37. The method as claimed in claim 24, wherein the component is preheated by a laser beam.

38. The method as claimed in claim 37, wherein the laser beam has a diameter from 2.5 mm to 5 mm.

39. The method as claimed in claim 37, wherein the laser beam has a power between 450 W to 950 W.

40. The method as claimed in claim 37, wherein a relative movement between the laser beam and the component is less than 1 nm/s.

41. The method as claimed in claim 37, wherein a relative movement between the laser beam and the component equals to 1 mm/s.

42. The method as claimed in claim 37, wherein the laser beam is a Nd-YAG laser.

43. The method as claimed in claim 24, wherein the welding method is a remelting process.