Pre-sintered preform for repair of service run gas turbine components

Patent metadata

Field	Value
Publication number	US-10760422-B2
Application number	US-201916512433-A
Country	US
Kind code	B2
Filing date	Jul 16, 2019
Priority date	Aug 9, 2018
Publication date	Sep 1, 2020
Grant date	Sep 1, 2020

Abstract

A pre-sintered preform ( 114 ) and a repair process ( 100 ) utilizing the pre-sintered preform ( 114 ) are disclosed, each of which result in a brazement ( 116 ) comprising a replacement protective coating ( 118 ) deposited on a component surface ( 110 ). The protective coating ( 118 ) exhibits excellent temperature and oxidation resistance, improved adhesion to superalloy surfaces, and reduced depletion over a service life of the associated component ( 102 ).

First claim

The invention claimed is:

1. A pre-sintered preform ( 114 ) comprising a sintered mixture of a bond coat powder and a braze powder, wherein the bond coat powder comprises by wt %:
Ni: 33.0-35.0;
Cr: 21.4-23.4;
Si: 8.6-9.2;
Al: 2.4-3.0;
W 1.2-1.6;
Ta 0.6-0.8;
B 0.45-0.65;
C 0.05-0.15;
Fe 0.15-0.45; and
Co balance
and wherein the braze powder comprises by wt %:
N 32;
C 21;
Al 8;
Y 0.5; and
Co balance.

2. The pre-sintered preform ( 114 ) of claim 1 , wherein the bond coat powder comprises by wt %:
Ni 34;
Cr 22.4;
Si 8.9;
Al 2.7;
W 1.4
Ta 0.7
B 0.55
C 0.12
Fe 0.3; and
Co balance.

3. The pre-sintered preform ( 114 ) of claim 1 , wherein the bond coat powder comprises from 0.01 to 0.3 by weight a member selected from the group consisting of Ti and Zr.

4. The pre-sintered preform ( 114 ) of claim 1 , wherein the bond coat powder and the braze powder comprise a 1:1 ratio by weight in the pre-sintered preform.

5. A bond coat composition comprising by wt %:
Ni: 33.0-35.0;
Cr: 21.4-23.4;
Si: 8.6-9.2;
Al: 2.4-3.0;
W 1.2-1.6;
Ta 0.6-0.8;
B 0.45-0.65;
C 0.05-0.15;
Fe 0.15-0.45; and
Co balance.

6. The bond coat composition of claim 5 , wherein the bond coat composition comprises by wt %:
Ni 34;
Cr 22.4;
Si 8.9;
Al 2.7;
W 1.4
Ta 0.7
B 0.55
C 0.12
Fe 0.3; and
Co balance.

Assignees

• Siemens Energy Inc

Inventors

• Ghunakikar Somesh J
• Yarbrough James A
• Garcia Mark A

Classifications

• C22C19/07

  based on cobalt · CPC title

• B23K35/30

  with the principal constituent melting at less than 1550°C · CPC title

• B23K1/00

  Soldering, e.g. brazing, or unsoldering (B23K3/00 takes precedence) · CPC title

• B23P6/00

  Restoring or reconditioning objects (straightening or restoring form of sheet metal, metal rods, metal tubes, metal profiles, or specific articles made therefrom B21D1/00, B21D3/00; repairing defective or damaged objects by casting techniques B22D19/10) · CPC title

• B23K1/20

  Preliminary treatment of work or areas to be soldered, e.g. in respect of a galvanic coating · CPC title