Advanced gamma TiAl components

Patent metadata

Field	Value
Publication number	US-9963977-B2
Application number	US-201514868903-A
Country	US
Kind code	B2
Filing date	Sep 29, 2015
Priority date	Sep 29, 2014
Publication date	May 8, 2018
Grant date	May 8, 2018

Abstract

Components include a low pressure turbine having a plurality of rotor assemblies including a first gamma TiAl intermetallic blade having a maximum operating temperature over 1180° F. (638° C.). At least two of the rotor assemblies include gamma TiAl intermetallic alloy blades. In an embodiment, a method of making a turbine having a plurality of rotor assemblies includes attaching a first gamma TiAl intermetallic alloy blade to an upstream stage of the plurality of rotor assemblies.

First claim

The invention claimed is:

1. A turbine having a plurality of rotor assemblies comprising:
a first gamma TiAl intermetallic alloy blade having a maximum operating temperature over 1180° F. (638° C.); and
hybrid vanes which include nickel alloy attachment and mounting features bonded to gamma TiAl intermetallic alloy airfoils, wherein bonding comprises isothermal transient liquid phase bonding.

2. The turbine of claim 1 , wherein the maximum operating temperature is over 1230° F. (666° C.).

3. The turbine of claim 1 , wherein maximum operating temperature of the first blade is between about 1230° F. (666° C.) and about 1330° F. (721° C.).

4. The turbine of claim 1 , wherein the first blade is operatively disposed in a last stage of the plurality of rotor assemblies.

5. The turbine of claim 1 , wherein the first blade is operatively disposed in a next to last stage of the plurality of rotor assemblies.

6. The turbine of claim 1 , further comprising at least one additional gamma TiAl intermetallic alloy blade having a maximum operating temperature over 1180° F. (638° C.), wherein the first and at least one of the additional blades are operatively disposed in respective upstream stages of the plurality of rotor assemblies.

7. The turbine of claim 6 , wherein at least one additional blade includes at least three gamma TiAl intermetallic alloy blades, each having a maximum operating temperature between about 1230° F. (666° C.) and about 1330° F. (721° C.).

8. The turbine of claim 6 , wherein the blades are formed from forged gamma TiAl intermetallic alloy.

9. The turbine of claim 8 , wherein the gamma TiAl intermetallic alloy has a composition of 42-45 at % Al, 3-5 at % Nb, 0.1-2 at % Mo, 0.1-1 at % B and the balance Ti.

10. The turbine of claim 9 , wherein the gamma TiAl intermetallic alloy has a composition of 43.5 at % Al, 4.0 at % Nb, 1.0 at % Mo, 0.2 at % B and the balance Ti.

11. The turbine of claim 1 , wherein a last stage of the plurality of rotor assemblies includes the first blade, has an exit annular area A, and is configured to rotate the first blade at a rotational speed N, and wherein A*N 2 is from between 5 and 7 (in·rpm) 2 (32-45 (cm·rpm) 2 ).

12. A method of making a turbine having a plurality of rotor assemblies comprising:
attaching a first gamma TiAl intermetallic alloy blade to an upstream stage of the plurality of rotor assemblies; and
forming hybrid vanes which include nickel alloy attachment and mounting features bonded to gamma TiAl intermetallic alloy airfoils, wherein bonding comprises isothermal transient liquid phase bonding.

13. The method of claim 12 , wherein the first blade has a maximum operating temperature between about 1230° F. (666° C.) and about 1330° F. (721° C.).

14. The method of claim 12 , wherein the first blade is forged from a gamma TiAl intermetallic alloy having a composition of 43.5 at % Al, 4.0 at % Nb, 1.0 at % Mo, 0.2 at % B and the balance Ti.

15. The method of claim 14 , wherein forging comprises isothermal forging at a temperature between about 2100° F. (1149° C.) and about 2240° F. (1227° C.).

16. The method of claim 12 , further comprising attaching a plurality of additional gamma TiAl intermetallic alloy blades to additional upstream stages of the plurality of rotor assemblies with each additional blade having a maximum operating temperature between about 1230° F. (666° C.) and about 1330° F. (721° C.).

17. The method of claim 12 , wherein the attachment and mounting features include hooks and platforms.

18. The method of claim 12 , wherein the bonding materials comprise a paste, foil, slurry or mixtures thereof.

Assignees

• United Technologies Corp

Inventors

• Suciu Gabriel L
• Hill James D
• Das Gopal

Classifications

• F05D2300/174

  Titanium alloys, e.g. TiAl · CPC title

• F05D2230/23

  by permanently joining parts together · CPC title

• F01D5/02

  Blade-carrying members, e.g. rotors (rotors of non-bladed type F01D1/34; stators F01D9/00 {; selecting particular materials F01D5/28}) · CPC title

• F05D2230/60

  Assembly methods · CPC title

• F01D5/147

  Construction, i.e. structural features, e.g. of weight-saving hollow blades (F01D5/148, F01D5/16 and F01D5/20 take precedence; blade shape F01D5/141; blades with cooling or heating channels or cavities F01D5/18; heating, heat-insulating or cooling means on blades F01D5/18) · CPC title