Beta titanium compositions and methods of manufacture thereof

• US 20040241037A1
• Filed: 06/16/2004
• Published: 12/02/2004
• Est. Priority Date: 06/27/2002
• Status: Abandoned Application

• Current Assignee: Memry Corporation
• Original Assignee: Memry Corporation
• Inventors: Wu, Ming H.
• Application Number:
  US10/869,359
• Publication Number:
  US 20040241037A1
• Time in Patent Office: Days
• US Class Current: 420/421
• CPC Class Codes: C22C 14/00 Alloys based on titanium
• CPC Class Codes: C22F 1/183 of titanium or alloys based thereon

Abstract

A composition comprises about 8 to about 12 wt % molybdenum, about 2.8 to about 6 wt % aluminum, up to about 2 wt % vanadium, up to about 4 wt % niobium, with the balance being titanium, wherein the weight percents are based on the total weight of the alloy composition. A method for making an article comprises cold-working a shape from a composition comprising about 8 to about 10 wt % molybdenum, about 2.8 to about 6 wt % aluminum, up to about 2 wt % vanadium, up to about 4 wt % niobium, with the balance being titanium, wherein the weight percents are based on the total weight of the alloy composition; solution heat treating the shape; and cooling the shape.

Claims

1. A method for producing an alloy composition comprising:

annealing the alloy composition; and

deforming the alloy composition at a temperature greater than ambient temperature to a temperature below that at which (x and w phase precipitates are formed;

wherein the composition comprises titanium; and

a molybdenum equivalent weight of about 7 to about 11 wt %, wherein the weight percents are based upon the total weight of the alloy composition.

2. The method of claim 1, wherein the molybdenum equivalent weight is determined by the equation (1)

Mo_eq.=1.00Mo+0.28Nb+0.22Ta+0.67V+1.43Co+1.60Cr+0.77Cu+2.9OFe+1.54Mn+1.11Ni+0.44W−

1.00Al  

 

(1)

or the equation (2)

Mo_eq.=1.00Mo+0.28Nb+0.22Ta+0.67V+1.43Co+1.60Cr+0.77Cu+2.9OFe+1.54Mn+1.11Ni+0.44W+0.25(Sn+Zr+Hf)−

1.00Al  

 

(2)

wherein Mo is molybdenum, Nb is niobium, Ta is tantalum, V is vanadium, Co is cobalt, Cr is chromium, Cu is copper, Fe is iron, Mn is manganese, Ni is nickel, W is tungsten, Al is aluminum, Sn is tin, Zr is zirconium and Hf is hafnium;

wherein aluminum can be substituted by gallium, carbon, germanium and/or boron; and

wherein the respective chemical symbols represent the amounts of the respective elements in weight percent based on the total weight of the alloy composition.

3. The method of claim 1, wherein the alloy composition comprises:

about 8 to about 12 wt % molybdenum,

about 2.8 to about 6 wt % aluminum,

up to about 2 wt % vanadium,

up to about 4 wt % niobium, with the balance being titanium, wherein the weight percents are based on the total weight of the alloy composition.

4. The method of claim 1, wherein the annealing is conducted at a temperature of about 800 to about 900°

C.

5. The method of claim 1, wherein the deforming is conducted at a temperature of about 50 to about 400°

C.

6. The method of claim 1, wherein the composition has an elastic modulus of 10% less than the elastic modulus of a similar composition that has been annealed but not subjected to the deforming of a forming operation.

7. The method of claim 1, wherein the composition has an elastic modulus of 20% less than the elastic modulus of a similar composition that has been annealed but not subjected to the deforming of a forming operation.

8. The method of claim 1, wherein the alloy composition has a β

phase and/or an α and

a β

phase.

21. An article manufactured by the method of claim 1.

9. A method for manufacturing an alloy composition having a high fatigue resistance comprising:

annealing the alloy composition; and

cold working the alloy composition;

wherein the composition comprises wherein the composition comprises titanium; and

a molybdenum equivalent weight of about 7 to about 11 wt %, wherein the weight percents are based upon the total weight of the alloy composition.

10. The method of claim 9, wherein the molybdenum equivalent weight is determined by the equation (1)

Mo_eq.=1.00Mo+0.28Nb+0.22Ta+0.67V+1.43Co+1.60Cr+0.77Cu+2.90Fe+1.54Mn+1.11Ni+0.44W−

1.00Al  

 

(1)

or the equation (2)

Mo_eq.=1.00Mo+0.28Nb+0.22Ta+0.67V+1.43Co+1.60Cr+0.77Cu+2.90Fe+1.54Mn+1.11Ni+0.44W+0.25(Sn+Zr+Hf)−

1.00Al  

 

(2)

wherein Mo is molybdenum, Nb is niobium, Ta is tantalum, V is vanadium, Co is cobalt, Cr is chromium, Cu is copper, Fe is iron, Mn is manganese, Ni is nickel, W is tungsten, Al is aluminum, Sn is tin, Zr is zirconium and Hf is hafnium;

wherein aluminum can be substituted by gallium, carbon, germanium and/or boron; and

wherein the respective chemical symbols represent the amounts of the respective elements in weight percent based on the total weight of the alloy composition.

11. The method of claim 9, wherein the alloy composition comprises:

about 8 to about 12 wt % molybdenum,

about 2.8 to about 6 wt % aluminum,

up to about 2 wt % vanadium,

up to about 4 wt % niobium, with the balance being titanium, wherein the weight percents are based on the total weight of the alloy composition.

12. The method of claim 9, wherein the cold working comprises a reduction in the cross-sectional area of greater than or equal to about 10 percent.

13. The method of claim 9, wherein the annealing is conducted at a temperature of about 800 to about 900°

C.

14. The method of claim 9, wherein the alloy composition has a fatigue resistance exceeding 10 million cycles at 0.75% bend strain.

22. An article manufactured by the method of claim 11.

15. An alloy composition comprising:

titanium; and

a molybdenum equivalent weight of about 7 to about 11 wt %, wherein the weight percents are based upon the total weight of the alloy composition;

wherein the composition is subjected to a process comprising annealing and deformation at a temperature greater than ambient temperature to a temperature below that at which a and ω

phase precipitates are formed.

16. The composition of claim 15, wherein the molybdenum equivalent weight is determined by the equation (1)

Mo_eq.=1.00Mo+0.28Nb+0.22Ta+0.67V+1.43Co+1.60Cr+0.77Cu+2.90Fe+1.54Mn+1.11Ni+0.44W−

1.00Al  

 

(1)

or the equation (2)

Mo_eq.=1.00Mo+0.28Nb+0.22Ta+0.67V+1.43Co+1.60Cr+0.77Cu+2.90Fe+1.54Mn+1.11Ni+0.44W+0.25(Sn+Zr+Hf)−

1.00Al  

 

(2)

wherein Mo is molybdenum, Nb is niobium, Ta is tantalum, V is vanadium, Co is cobalt, Cr is chromium, Cu is copper, Fe is iron, Mn is manganese, Ni is nickel, W is tungsten, Al is aluminum, Sn is tin, Zr is zirconium and Hf is hafnium;

wherein aluminum can be substituted by gallium, carbon, germanium and/or boron; and

wherein the respective chemical symbols represent the amounts of the respective elements in weight percent based on the total weight of the alloy composition.

17. The composition of claim 15, wherein the alloy composition comprises:

about 8 to about 12 wt % molybdenum,

about 2.8 to about 6 wt % aluminum,

up to about 2 wt % vanadium,

up to about 4 wt % niobium, with the balance being titanium, wherein the weight percents are based on the total weight of the alloy composition.

23. An article manufactured by the composition of claim 15.

18. An alloy composition comprising:

titanium; and

a molybdenum equivalent weight of about 7 to about 11 wt %, wherein the weight percents are based upon the total weight of the alloy composition;

wherein the composition is subjected to a process comprising annealing and cold working.

19. The composition of claim 18, wherein the molybdenum equivalent weight is determined by the equation (1)

Mo_eq.=1.00Mo+0.28Nb+0.22Ta+0.67V+1.43Co+1.60Cr+0.77Cu+2.90Fe+1.54Mn+1.11Ni+0.44W−

1.00Al  

 

(1)

or the equation (2)

Mo_eq.=1.00Mo+0.28Nb+0.22Ta+0.67V+1.43Co+1.60Cr+0.77Cu+2.90Fe+1.54Mn+1.11Ni+0.44W+0.25(Sn+Zr+Hf)−

1.00Al  

 

(2)

wherein Mo is molybdenum, Nb is niobium, Ta is tantalum, V is vanadium, Co is cobalt, Cr is chromium, Cu is copper, Fe is iron, Mn is manganese, Ni is nickel, W is tungsten, Al is aluminum, Sn is tin, Zr is zirconium and Hf is hafnium;

wherein aluminum can be substituted by gallium, carbon, germanium and/or boron; and

wherein the respective chemical symbols represent the amounts of the respective elements in weight percent based on the total weight of the alloy composition.

20. The composition of claim 18, wherein the alloy composition comprises:

about 8 to about 12 wt % molybdenum,

about 2.8 to about 6 wt % aluminum,

up to about 2 wt % vanadium,

up to about 4 wt % niobium, with the balance being titanium, wherein the weight percents are based on the total weight of the alloy composition.

24. An article manufactured by the composition of claim 18.