Method for manufacturing a turbine shroud for a turbomachine

Patent metadata

Field	Value
Publication number	US-10843271-B2
Application number	US-201716084567-A
Country	US
Kind code	B2
Filing date	Mar 10, 2017
Priority date	Mar 14, 2016
Publication date	Nov 24, 2020
Grant date	Nov 24, 2020

Abstract

The invention relates to a method for manufacturing a turbine shroud (24) for a turbomachine, the method comprising manufacturing at least one turbine shroud sector (28), positioning the turbine shroud sector (26) in a bottom mold so that an outer surface of the turbine shroud sector is in contact at least in part with the bottom mold, and depositing a powder layer on an inner surface (28) of the turbine shroud sector (26). Thereafter, a top mold is positioned on the powder layer and an abradable layer (32) is made by subjecting the powder layer to a method of SPS sintering, the abradable layer (32) being for being disposed facing a turbine wheel.

First claim

The invention claimed is:

1. A method for manufacturing a turbine shroud for a turbomachine, the method comprising the following steps:
manufacturing at least one turbine shroud sector;
positioning the turbine shroud sector in a bottom mold so that an outer surface of the turbine shroud sector is in contact at least in part with the bottom mold;
depositing a powder layer on an inner surface of the turbine shroud sector;
positioning a top mold on the powder layer; and
making an abradable layer on the inner surface by subjecting the powder layer to a method of SPS sintering, the abradable layer being for being disposed facing a turbine wheel;
wherein before positioning the turbine shroud sector in the bottom mold and the top mold, a layer of chemically inert material is deposited on the bottom mold and on the top mold.

2. The method according to claim 1 , further comprising the following steps:
assembling together a plurality of turbine shroud sectors, the inner surface of each turbine shroud sector being covered in an abradable layer; and
machining a free surface of the abradable layer.

3. The method according to claim 1 , wherein the bottom mold is of shape complementary to the outer surface of the turbine shroud sector.

4. The method according to claim 1 , wherein the powder is a metal powder based on cobalt or on nickel.

5. The method according to claim 1 , wherein the SPS sintering is performed for a duration shorter than or equal to 60 minutes.

6. The method according to claim 1 , wherein the top mold and the bottom mold are made of graphite, and wherein the SPS sintering is performed at a temperature higher than or equal to 800° C.

7. The method according to claim 6 , wherein the SPS sintering is performed at a pressure higher than or equal to 10 MPa.

8. The method according to claim 1 , wherein the top mold and the bottom mold are made of tungsten carbide, and wherein the SPS sintering is performed at a temperature higher than or equal to 500° C.

9. The method according to claim 8 , wherein the SPS sintering is performed at a pressure higher than or equal to 100 MPa.

Assignees

• Safran Aircraft Engines
• Centre Nat Rech Scient
• Univ Paul Sabatier—Toulouse Iii

Inventors

• Mottin Jean-Baptiste
• Beynet Yannick Marcel
• Chevallier Geoffroy
• Epherre Romain
• Estournes Claude

Classifications

• F01D11/122

  with erodable or abradable material (blades having cutting or grinding tips F01D5/20) · CPC title

• B22F2207/01

  Composition gradients · CPC title

• B22F7/06

  of composite workpieces or articles from parts, e.g. to form tipped tools {(B22F7/002 takes precedence)} · CPC title

• B22F3/24

  After-treatment of workpieces or articles {(B22F3/1146 takes precedence)} · CPC title

• F05D2240/11

  Shroud seal segments · CPC title