Abrasive blade tip treatment

Patent metadata

Field	Value
Publication number	US-10183312-B2
Application number	US-201514706369-A
Country	US
Kind code	B2
Filing date	May 7, 2015
Priority date	May 23, 2014
Publication date	Jan 22, 2019
Grant date	Jan 22, 2019

Abstract

An abrasive coating for a metal airfoil tip in a gas turbine engine may include a plurality of grit particles coated with a braze alloy material and configured for attachment to the airfoil tip. The braze alloy may be a nickel base, cobalt base or iron base braze alloy or mixtures thereof, or a titanium base braze alloy.

First claim

The invention claimed is:

1. A method of forming an abrasive layer on an outermost radial tip surface of a metal airfoil in a gas turbine engine, the outermost radial tip surface being configured as the only portion of the metal airfoil to form an abradable seal with a shroud during operation of the engine, the method comprising:
depositing a plurality of grit particles coated with a braze alloy on the outermost radial tip surface of the metal airfoil; and
heating preselected regions of the outermost radial tip surface after the depositing by directing an energy beam to melt the braze alloy to produce an areal patterned layer of grit particles attached to the outermost radial tip surface;
wherein the areal patterned layer of grit particles consists of a stripe down a center of the outermost radial tip surface of the metal airfoil.

2. The method of claim 1 , wherein the grit particles are selected from the group consisting of cubic boron nitride (CBN), zirconia, alumina, silicon carbide, and diamond.

3. The method of claim 1 , wherein the braze alloy comprises a nickel base, cobalt base, or iron base braze alloy or mixtures thereof, or a titanium base braze alloy.

4. The method of claim 1 , wherein the energy beam is a laser or electron beam.

5. The method of claim 1 , wherein the patterned layer of grit particles is attached to the outermost radial tip surface by a braze alloy layer after the molten braze alloy solidifies.

6. The method of claim 1 wherein the areal patterned layer covers 10 percent of the outermost radial tip surface of the metal airfoil.

Assignees

• United Technologies Corp

Inventors

• Strock Christopher W
• Guo Changsheng

Classifications

• B23K1/0018 Primary

  Brazing of turbine parts · CPC title

• B22F10/28

  Powder bed fusion, e.g. selective laser melting [SLM] or electron beam melting [EBM] · CPC title

• B05D5/00 Primary

  Processes for applying liquids or other fluent materials to surfaces to obtain special surface effects, finishes or structures · CPC title

• F01D11/122

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

• B23K35/3046

  Co as the principal constituent · CPC title