Method for cleaning and stripping a turboshaft engine blade using a pulsed laser

Patent metadata

Field	Value
Publication number	US-9415462-B2
Application number	US-201214114836-A
Country	US
Kind code	B2
Filing date	May 2, 2012
Priority date	May 2, 2011
Publication date	Aug 16, 2016
Grant date	Aug 16, 2016

Abstract

A method for cleaning a turboshaft engine blade comprising a superalloy body covered with a coating, in which the coating of the blade is at least partially machined using a pulsed laser. At least the feed rate of the pulsed laser and the pulse frequency of the pulsed laser are parameterized such that the machined surface of the blade has a roughness of 4 μm to 10 μm.

First claim

The invention claimed is:

1. A method for cleaning and stripping a turboshaft engine blade comprising a superalloy body covered with a coating, comprising:
identifying a portion of the coating to remove, the coating including a metal layer covering the body of the blade and an external ceramic layer covering the metal layer; and
machining, at least partially, the coating of the blade using a pulsed laser to remove at least the external ceramic layer of the coating,
wherein a feed rate of the pulsed laser and a pulse frequency of the pulsed laser are parameterized such that a machined surface of the blade has a roughness of 4 μm to 10 μm.

2. The method according to claim 1 , wherein the pulsed laser is parameterized in order to remove only the external ceramic layer.

3. The method according to claim 1 , wherein the pulsed laser is parameterized in order to remove only the external ceramic layer and the metal layer.

4. The method according to claim 1 , wherein the pulsed laser is parameterized in order to remove the entire coating of the blade.

5. The method according to claim 1 , wherein the feed rate of the pulsed laser is between 25 mm/s and 1000 mm/s.

6. The method according to claim 5 , wherein the feed rate of the pulsed laser is between 100 mm/s and 600 mm/s.

7. The method according to claim 1 , wherein the pulse frequency of the pulsed laser is between 12 kHz and 50 kHz.

8. The method according to claim 7 , wherein the pulse frequency of the pulse laser is less than or equal to 16 kHz.

9. The method according to claim 1 , wherein the roughness is constant over the machined coating.

10. The method according to claim 1 , wherein the coating comprises a plurality of layers, the pulsed laser machines the layers of the coating by carrying out a plurality of machining passes, and the number of machining passes for a layer is defined as a function of a thickness of the layer and a hardness of a material of the layer.

11. The method according to claim 1 , wherein the pulsed laser is moved along machining lines on the coating, and two consecutive machining lines overlap.

12. The method according to claim 1 , wherein a controller moves the pulsed laser in the course of the machining along a defined trajectory based on three-dimensional modeling of the blade to be cleaned.

13. The method according to claim 1 , wherein the superalloy body of the blade is not removed by the machining.

14. The method according to claim 1 , wherein a width of the pulsed laser is less than or equal to 0.05 mm.

15. The method according to claim 1 , wherein the metal layer has a thickness between 50 and 100 μm and the external ceramic layer has a thickness between 150 and 350 μm.

Assignees

• Hugot Juliette
• Bourdin Franck
• Fevrier Thierry
• Gestin Jerome
• Snecma

Inventors

• Hugot Juliette
• Bourdin Franck
• Fevrier Thierry
• Gestin Jerome

Classifications

• F01D25/002

  Cleaning of turbomachines · CPC title

• B23K26/0006 Primary

  taking account of the properties of the material involved (B23K26/32, B23K26/40 take precedence) · CPC title

• B23K2203/172

  Operations & Transport · mapped topic

• B23K2203/08

  Operations & Transport · mapped topic

• B23K26/362

  Laser etching · CPC title