Titanium-based alloy

• US 20100086794A1
• Filed: 09/23/2009
• Published: 04/08/2010
• Est. Priority Date: 09/23/2008
• Status: Active Grant

• Current Assignee: Sandvik Intellectual Property AB (Sandvik AB)
• Original Assignee: Sandvik Intellectual Property AB (Sandvik AB)
• Inventors: Norgren, Susanne
• Granted Patent: US 8,492,002 B2
• Time in Patent Office: Days
• US Class Current: 428/469
• CPC Class Codes: A61L 27/06 Titanium or titanium alloys
• CPC Class Codes: A61L 31/022 Metals or alloys
• CPC Class Codes: C22C 14/00 Alloys based on titanium
• CPC Class Codes: C22F 1/183 of titanium or alloys based thereon

Abstract

An alloy having from about 5 to about 15 wt % Ta, from 0 to about 5 wt % Nb, from about 0.5 to about 15 wt % Zr, and the balance Ti is disclosed. The alloy is particularly intended for medical devices, such as implants for the body.

Claims

1. Alloy comprising from about 5 to about 15 wt % Ta, from 0 to about 5 wt % Nb, from about 0.5 to about 15 wt % Zr, and the balance Ti and incidental impurities.

2. Alloy according to claim 1, wherein the alloy comprises from about 7 to about 13 wt % Ta, from about 0.5 to about 3 wt % Nb, from about 1 to about 10 wt % Zr, and the balance Ti and incidental impurities.

3. Alloy according to claim 1, wherein the alloy comprises about 10.3 wt % Ta, about 1.6 wt % Nb, about 1.7 wt % Zr, and the balance Ti and incidental impurities.

4. Alloy according to claim 1, wherein the alloy comprises about 10.3 wt % Ta, about 1.6 wt % Nb, about 8 wt % Zr, and the balance Ti and incidental impurities.

5. Alloy according to claim 1, wherein the weight ratio Nb/Ta in the alloy is from about 0.05 to about 1.

6. Alloy according to claim 1, wherein the content of Ti in the alloy is from about 75 to about 91 wt %.

7. Alloy according to claim 1, wherein the content of Ti in the alloy is at least 85 at %.

8. Alloy according to claim 1, wherein the alloy is an alpha+beta alloy wherein the content of beta-phase in the alloy is from about 10 to about 60 vol %.

9. Alloy according to claim 1, wherein the hardness of the alloy, according to Vickers hardness test, is at least about 250 HV3.

10. Alloy according to claim 1, wherein the surface of the alloy comprises a crystalline oxide layer.

11. Medical device composed of the alloy according to claim 1.

12. Medical device according to claim 11, which is an implant for the human or animal body.

13. Method for preparing an alloy comprising from about 5 to about 15 wt % Ta, from 0 to about 5 wt % Nb, from about 0.5 to about 15 wt % Zr, and the balance Ti and incidental impurities, comprising melting together the elements Ti, Ta, Zr, and optionally Nb, followed by cooling to solidify the alloy formed.

14. Method according to claim 13, wherein the alloy comprises about 10.3 wt % Ta, about 1.6 wt % Nb, about 1.7 wt % Zr, and the balance Ti and incidental impurities.

15. Method according to claim 13, wherein the alloy comprises about 10.3 wt % Ta, about 1.6 wt % Nb, about 8 wt % Zr, and the balance Ti and incidental impurities.

16. Method according to claim 13, wherein the content of Ti in the alloy is at least 85 at %.

17. Method according to claim 13, wherein the alloy is an alpha₊beta alloy wherein the content of beta-phase in the alloy is from about 10 to about 60 vol %.

18. Method according to claim 13, wherein the hardness of the alloy, according to Vickers hardness test, is at least about 250 HV3.

19. Method according to claim 13, further comprising heat treatment of the solidified alloy, comprising heating the alloy to a temperature of from about 500 to about 1000°

C., the duration of the heat treatment is at least about 0.25 hour, whereafter the alloy is rapidly cooled down at a rate of at least about 5°

C./min until room temperature is reached.

20. Method according to claim 13, further comprising oxidising the surface of the alloy.