Braze alloy compositions and brazing methods for superalloys

Patent metadata

Field	Value
Publication number	US-9664049-B2
Application number	US-201314070626-A
Country	US
Kind code	B2
Filing date	Nov 4, 2013
Priority date	Nov 4, 2013
Publication date	May 30, 2017
Grant date	May 30, 2017

Abstract

A multi-component braze filler alloy comprising at least 70% by weight MarM509A superalloy with the remainder MarM509B superalloy is diffusion brazed to a CM247 alloy base substrate, such as a gas turbine blade or vane. It is shown that generally higher braze temperatures lead to improved results including the possibility of re-welding such a brazed component, resulting in a re-repaired brazed component capable of continued commercial service.

First claim

What is claimed is:

1. A method for brazing an Ni base superalloy component comprising, in the following order:
placing the Ni base superalloy component to be brazed and the brazing material into a brazing furnace, properly configured to perform the desired brazing process upon heating; and
increasing the furnace temperature to within about 25 deg. F of 1800 deg. F at a rate of approximately 28 deg. F per minute; and
reducing the pressure within the furnace to less than about 0.005 Torr and hold for stabilization; and
increasing the furnace temperature to within about 12 deg. F of 2270 deg. F at a rate no greater than about 10 deg. F per min. and hold at this temperature for about 240 to 255 minutes for combined braze and diffusion cycle time while maintaining the pressure no greater than about 0.005 Torr; and
vacuum cooling the furnace temperature to within about 25 deg. F of 1975 deg. F in a time no more than about 3 minutes; and
rapid cooling to room temperature by back purging with inert gas; and,
wherein the brazing material comprises:
a mixture of no less than approximately 70% by weight of a base alloy comprising, by weight:
C: X C =0.6%;
Cr: X Cr =24%;
Ni: X Ni =10%;
W: X W =7%;
Ta: X Ta =3.5%;
Co: X Co =(balance) and the balance comprising a braze alloy comprising:
C: X C =0.6%;
Cr: X Cr =23%;
Ni: X Ni =10%;
W: X W =7%;
Ta: X Ta =3.5%;
B: X B =2.5%;
Co: X Co =(balance);

the mixture including about 10%-15% by volume of a liquid binder to form a paste.

2. The method of claim 1 , wherein the Ni base superalloy turbine component comprises, by weight:
C: X C =0.07-0.15%;
Cr: X Cr =8.1-8.4%;
Co: X Co =9.2-10.0%;
Al: X Al =5.5-5.6%;
B: X B =0.015%;
W: X W =9.5-10.0%;
Mo: X Mo =0.5-0.7%;
Ta: X Ta =3.0-3.2%;
Ti: X Ti =0.7-1.0%;
Hf: X Hf =1.4-1.5%;
Zr: X Zr =0.015-0.05%;
Ni: X Ni =(balance).

3. The method of claim 1 , wherein the Ni base superalloy component is a turbine vane or blade.

4. The method of claim 1 , further comprising re repairing the superalloy component by post braze welding and designating the superalloy component as suitable for continued service.

5. The method of claim 4 , wherein the Ni base superalloy turbine component comprises, by weight:
C: X C =0.07-0.15%;
Cr: X Cr =8.1-8.4%;
Co: X Co =9.2-10.0%;
Al: X Al =5.5-5.6%;
B: X B =0.015%;
W: X W =9.5-10.0%;
Mo: X Mo =0.5-0.7%;
Ta: X Ta =3.0-3.2%;
Ti: X Ti =0.7-1.0%;
Hf: X Hf =1.4-1.5%;
Zr: X Zr =0.015-0.05%;
Ni: X Ni =(balance).

6. The method of claim 4 , wherein the Ni base superalloy component is a turbine vane or blade.

7. The method of claim 1 , further comprising post braze heat treatment of the superalloy component and designating the superalloy component as suitable for continued service.

8. The method of claim 7 , wherein the Ni base superalloy turbine component comprises, by weight:
C: X C =0.07-0.15%;
Cr: X Cr =8.1-8.4%;
Co: X Co =9.2-10.0%;
Al: X Al =5.5-5.6%;
B: X B =0.015%;
W: X W =9.5-10.0%;
Mo: X Mo =0.5-0.7%;
Ta: X Ta =3.0-3.2%;
Ti: X Ti =0.7-1.0%;
Hf: X Hf =1.4-1.5%;
Zr: X Zr =0.015-0.05%;
Ni: X Ni =(balance).

9. The method of claim 7 , wherein the Ni base superalloy component is a turbine vane or blade.

Assignees

• Siemens Energy Inc

Inventors

• Georgieva Petya M
• Yarbrough James A

Classifications

• B23K35/3046

  Co as the principal constituent · CPC title

• C22C19/07

  based on cobalt · CPC title

• B23K35/025

  Pastes, creams or slurries · CPC title

• F01D9/02

  Nozzles; Nozzle boxes; Stator blades; Guide conduits {, e.g. individual nozzles (nozzle boxes F01D9/047)} · CPC title

• B23K35/36

  Selection of non-metallic compositions, e.g. coatings or fluxes (B23K35/34 takes precedence); Selection of soldering or welding materials, conjoint with selection of non-metallic compositions, both selections being of interest · CPC title