Metastable β-titanium alloys and methods of processing the same by direct aging

• US 9,523,137 B2
• Filed: 11/19/2013
• Issued: 12/20/2016
• Est. Priority Date: 05/21/2004
• Status: Active Grant

• Current Assignee: ATI Properties LLC
• Original Assignee: ATI Properties LLC
• Inventors: Marquardt, Brian, Wood, John Randolph, Freese, Howard L., Jablokov, Victor R.
• Primary Examiner(s): Roe, Jessee
• Application Number:
  US14/083,759
• Publication Number:
  US 20140076468A1
• Time in Patent Office: 1,127 Days
• US Class Current: 1/1
• CPC Class Codes: C22C 14/00 Alloys based on titanium
• CPC Class Codes: C22F 1/183 of titanium or alloys based thereon

Abstract

Metastable beta titanium alloys and methods of processing metastable β-titanium alloys are disclosed. For example, certain non-limiting embodiments relate to metastable β-titanium alloys, such as binary β-titanium alloys comprising greater than 10 weight percent molybdenum, having tensile strengths of at least 150 ksi and elongations of at least 12 percent. Other non-limiting embodiments relate to methods of processing metastable β-titanium alloys, and more specifically, methods of processing binary β-titanium alloys comprising greater than 10 weight percent molybdenum, wherein the method comprises hot working and aging the metastable β-titanium alloy at a temperature below the β-transus temperature of the metastable β-titanium alloy for a time sufficient to form α-phase precipitates in the metastable β-titanium alloy. The metastable β-titanium alloys are not solution heat treated after hot working and prior to aging. Articles of manufacture comprising binary β-titanium alloys according to various non-limiting embodiments disclosed herein are also disclosed.

Claims

1. A metastable β

-titanium alloy consisting of;

titanium;

greater than 10 weight percent molybdenum; and

incidental impurities;

the metastable β

-titanium alloy having a tensile strength of at least 150 ksi, an elongation of at least 12 percent, and a microstructure comprising a uniform distribution of α

-phase precipitates in metastable phase regions of the metastable β

-titanium alloy;

wherein the α

-phase precipitates comprise coarse grain size α

-phase precipitates and fine grain size α

-phase precipitates, and wherein an average grain size of the coarse grain size α

-phase precipitates is larger than an average grain size of the fine grain size α

-phase precipitates.

2. The metastable β

-titanium alloy of claim 1, wherein the metastable β

-titanium alloy has a tensile strength of 150 ksi to 180 ksi and an elongation of 12 percent to 20 percent.

3. The metastable β

-titanium alloy of claim 1, wherein the metastable β

-titanium alloy has a rotating beam fatigue strength of at least 650 MPa.

4. The metastable β

-titanium alloy of claim 1, wherein the metastable β

-titanium alloy consists of titanium, at least 14 weight percent molybdenum, and incidental impurities.

5. The metastable β

-titanium alloy of claim 4, wherein the metastable β

-titanium alloy has a tensile strength of 150 ksi to 180 ksi and an elongation of 12 percent to 20 percent.

6. The metastable β

-titanium alloy of claim 4, wherein the metastable β

-titanium alloy has a rotating beam fatigue strength of at least 650 MPa.

7. The metastable β

-titanium alloy of claim 4, wherein the metastable β

-titanium alloy has a tensile strength of at least 180 ksi and an elongation of at least 17 percent.

8. An article of manufacture comprising:

a metastable β

-titanium alloy consisting of titanium, greater than 10 weight percent molybdenum, and incidental impurities, the metastable β

-titanium alloy having a tensile strength of at least 150 ksi, an elongation of at least 12 percent, and a microstructure comprising a uniform distribution of α

-phase precipitates in metastable phase regions of the metastable β

-titanium alloy, wherein the α

-phase precipitates comprise coarse grain size α

-phase precipitates and fine grain size α

-phase precipitates, and wherein an average grain size of the coarse grain size α

-phase precipitates is larger than an average grain size of the fine grain size α

-phase precipitates.

9. The article of manufacture of claim 8, wherein the article of manufacture is selected from a biomedical component, an automotive component, an aerospace component, a chemical processing component, and a nautical component.

10. The article of manufacture of claim 8, wherein the article of manufacture is selected from a hip stem, a femoral hip stem, a femoral head, a modular ball, a bone screw, a cannulated screw, a hollow screw, a tibial tray, a knee component, a dental implant, and an intermedullary nail.

11. The article of manufacture of claim 8, where the article of manufacture is selected from a wire and a cable.

12. The article of manufacture of claim 8, wherein the metastable β

-titanium alloy consists of titanium, at least 14 weight percent molybdenum, and incidental impurities.

13. The article of manufacture of claim 12, wherein the article of manufacture is selected from a biomedical component, an automotive component, an aerospace component, a chemical processing component, and a nautical component.

14. The article of manufacture of claim 12, wherein the article of manufacture is selected from a biomedical component comprising at least one of a hip stem, a femoral hip stem, a femoral head, a modular ball, a bone screw, a cannulated screw, a hollow screw, a tibial tray, a knee component, a dental implant, and an intermedullary nail.

15. The article of manufacture of claim 12, where the article of manufacture is selected from a wire and a cable.

16. A metastable β

-titanium alloy consisting of;

titanium;

at least 14 weight percent molybdenum; and

incidental impurities;

the metastable β

-titanium alloy having a tensile strength of at least 180 ksi, an elongation of at least 17 percent, and a microstructure comprising a uniform distribution of α

-phase precipitates in metastable phase regions of the metastable β

-titanium alloy.

17. The metastable β

-titanium alloy of claim 16, wherein the metastable β

-titanium alloy has a rotating beam fatigue strength of at least 650 MPa.

18. The metastable β

-titanium alloy of claim 16, wherein the metastable β

-titanium alloy has an elongation of 17 percent to 20 percent.

19. An article of manufacture comprising:

a metastable β

-titanium alloy consisting of titanium, at least 14 weight percent molybdenum, and incidental impurities, the metastable β

-titanium alloy having a tensile strength of at least 180 ksi, an elongation of at least 17 percent, and a microstructure comprising a uniform distribution of α

-phase precipitates in metastable phase regions of the metastable β

-titanium alloy.

20. The article of manufacture of claim 19, wherein the article of manufacture is selected from a biomedical component, an automotive component, an aerospace component, a chemical processing component, and a nautical component.

21. The article of manufacture of claim 19, wherein the article of manufacture is selected from a hip stem, a femoral hip stem, a femoral head, a modular ball, a bone screw, a cannulated screw, a hollow screw, a tibial tray, a knee component, a dental implant, and an intermedullary nail.

22. The article of manufacture of claim 19, wherein the article of manufacture is selected from a wire and a cable.

23. The article of manufacture of claim 19, wherein the α

-phase precipitates comprise coarse grain size α

-phase precipitates and fine grain size α

-phase precipitates, and wherein an average grain size of the coarse grain size α

-phase precipitates is larger than an average grain size of the fine grain size α

-phase precipitates.

24. The article of manufacture of claim 23, wherein the article of manufacture is selected from a wire and a cable.

25. An article of manufacture comprising:

a metastable β

-titanium alloy consisting of titanium, greater than 10 weight percent molybdenum, and incidental impurities, the metastable β

-titanium alloy having a tensile strength of at least 150 ksi, an elongation of at least 12 percent, and a microstructure comprising a uniform distribution of α

-phase precipitates in metastable phase regions of the metastable β

-titanium alloy, wherein the article of manufacture is selected from a wire and a cable.

26. The article of manufacture of claim 25, wherein the metastable β

-titanium alloy consists of titanium, at least 14 weight percent molybdenum, and incidental impurities.