Titanium alloy having good oxidation resistance and high strength at elevated temperatures

Patent metadata

Field	Value
Publication number	US-11041402-B2
Application number	US-201815903545-A
Country	US
Kind code	B2
Filing date	Feb 23, 2018
Priority date	Jul 19, 2012
Publication date	Jun 22, 2021
Grant date	Jun 22, 2021

Abstract

A titanium alloy may be characterized by a good oxidation resistance, high strength and creep resistance at elevated temperatures up to 750° C., and good cold/hot forming ability, good superplastic forming performance, and good weldability. The alloy may contain, in weight percent, aluminum 4.5 to 7.5, tin 2.0 to 8.0, niobium 1.5 to 6.5, molybdenum 0.1 to 2.5, silicon 0.1 to 0.6, oxygen up to 0.20, carbon up to 0.10, and balance titanium with incidental impurities.

First claim

The invention claimed is:

1. A method comprising:
preparing a titanium alloy consisting essentially of, by weight, 4.5 to 7.5% aluminum, 2.0 to 8.0% tin, 1.5 to 6.5% niobium, 0.1 to 2.5% molybdenum, 0.1 to 0.6% silicon, and a total of zirconium and vanadium in a range of 0.0 to 0.5% balance titanium;
solution heat treating the titanium alloy; and
forming the titanium alloy into a shaped aerospace component, wherein the forming is selected from the group consisting of: hot forming, cold forming, superplastic forming, and combinations thereof.

2. The method of claim 1 , where the forming is cold forming.

3. The method of claim 1 , where the forming is hot forming.

4. The method of claim 1 , where the forming is superplastic forming.

5. The method of claim 1 , wherein the solution heat treating comprises heating to produce a bimodal I microstructure.

6. The method of claim 1 , wherein the shaped aerospace component is an engine component.

7. The method of claim 1 , wherein the shaped aerospace component is a pylon component.

8. The method of claim 1 , wherein the shaped aerospace component is a fastener component.

9. The method of claim 8 , wherein the fastener component is a threaded fastener.

10. The method of claim 1 , comprising, prior to the solution heat treating step, hot working the titanium alloy to a final gauge product.

11. The method of claim 10 , wherein the hot working comprises hot rolling.

12. The method of claim 1 , comprising:
operating a machine comprising the shaped aerospace component so the titanium alloy component is continuously maintained at a temperature of at least 600° C. for a duration of at least 30 minutes.

13. The method of claim 1 , wherein the solution heat treating comprises heating to produce a bimodal II microstructure.

14. The method of claim 1 , wherein the solution heat treating comprises heating to produce an equiaxed microstructure.

Assignees

• Rti Int Metals Inc
• Howmet Aerospace Inc

Inventors

• Sun Fusheng
• Crist Ernest M
• Yu Kuang-O

Classifications

• C22C14/00 Primary

  Alloys based on titanium · CPC title

• C22C1/02

  by melting {(C22C1/1036 takes precedence)} · CPC title

• F01D5/28

  Selecting particular materials; {Particular measures relating thereto;} Measures against erosion or corrosion · CPC title

• F01D25/005 Primary

  Selecting particular materials · CPC title

• C22F1/183

  of titanium or alloys based thereon · CPC title