Article and method of manufacturing the same

Patent metadata

Field	Value
Publication number	US-11701754-B2
Application number	US-202117176456-A
Country	US
Kind code	B2
Filing date	Feb 16, 2021
Priority date	Feb 21, 2020
Publication date	Jul 18, 2023
Grant date	Jul 18, 2023

Abstract

An article and a method of manufacturing the article is disclosed. The method includes providing the article including a substrate and a coating at least partially disposed on the substrate. The coating includes an outer surface. The coating further includes platinum and chromium. The method further includes applying cold work to the outer surface of the coating to produce a cold-worked layer extending from the outer surface of the coating to a cold work depth. The cold-worked layer includes approximately 45% cold work. The cold work depth is between about 30 microns to about 150 microns from the outer surface of the coating.

First claim

We claim:

1. A method of manufacturing an article, the method comprising the steps of:
providing an article comprising a substrate and a PtCr coating at least partially disposed on the substrate, the PtCr coating comprising an outer surface and a single gamma phase outer zone, the PtCr coating comprising platinum and about 8 wt. % to about 30 wt. % of chromium, wherein the PtCr coating is formed by a process comprising depositing a platinum layer having a thickness of 4 to 7 microns on the substrate and following formation of the platinum layer, a layer of chromium is deposited onto the platinum using a chemical vapor deposition process (CVD) to diffuse in the chromium which interdiffuses the chromium with the platinum to form a single gamma phase structure, the single phase structure forming the single gamma phase outer zone of the PtCr coating; and
applying cold work to the outer surface of the PtCr coating to produce a cold-worked layer extending from the outer surface of the PtCr coating to a cold work depth, wherein the cold-worked layer of the article comprises approximately 45% cold work, and wherein the cold work depth is between about 30 microns to about 150 microns from the outer surface of the PtCr coating; wherein
the article is a turbine blade.

2. The method of claim 1 , wherein applying cold work further comprises shot peening the outer surface of the PtCr coating using shot.

3. The method of claim 2 , wherein an intensity of shot peening is between about 2A to about 12A, and wherein the intensity of shot peening is imperial intensity such that 2A is equivalent to 0.002 inches and 12A is equivalent to 0.012 inches.

4. The method of claim 2 , wherein the shot is between about 070H to about 330H conforming to at least one of AMS2431/1, AMS2431/2, AMS2431/3, AMS2431/4, AMS2431/5, AMS2431/5, AMS2431/6, AMS2431/7, and AMS2431/8 specifications.

5. The method of claim 2 , wherein a coverage of shot peening is between about 95% to about 1200%.

6. The method of claim 1 , wherein applying cold work further comprises deep cold rolling the outer surface of the PtCr coating.

7. The method of claim 1 , wherein the cold-worked layer further comprises a chromia scale extending from the outer surface of the PtCr coating, and wherein a thickness of the chromia scale is less than the cold work depth.

8. The method of claim 7 , wherein the thickness of the chromia scale is less than a thickness of the PtCr coating.

9. The method of claim 8 , wherein the cold work depth is greater than the thickness of the PtCr coating.

10. The method of claim 1 , wherein the turbine blade comprises an aerofoil, a platform, a shank and a root, and wherein the PtCr coating is disposed on the shank and the root of the turbine blade.

Assignees

• Rolls Royce Plc

Inventors

• Leggett Andrew J
• Gibson Grant J

Classifications

• B24C1/10 Primary

  for compacting surfaces, e.g. shot-peening (for deforming sheet metal, tubes or profiles B21D31/06; as a metallurgical treatment C21D7/00, C22F1/00) · CPC title

• C23C30/00 Primary

  Coating with metallic material characterised only by the composition of the metallic material, i.e. not characterised by the coating process (C23C26/00, C23C28/00 take precedence) · CPC title

• C23C28/321

  with at least one metal alloy layer · CPC title

• C23C28/322

  only coatings of metal elements only · CPC title

• C23C28/345

  with at least one oxide layer · CPC title