Method of providing a zirconium surface and resulting product

• US 8,556,987 B2
• Filed: 12/17/2010
• Issued: 10/15/2013
• Est. Priority Date: 09/16/2004
• Status: Active Grant

• Current Assignee: Smith & Nephew Incorporated (Smith & Nephew PLC)
• Original Assignee: Smith & Nephew Incorporated (Smith & Nephew PLC)
• Inventors: Hunter, Gordon, Jani, Shilesh C., Pawar, Vivek
• Primary Examiner(s): Stewart, Alvin J.
• Application Number:
  US12/971,933
• Publication Number:
  US 20110139312A1
• Time in Patent Office: 1,033 Days
• Field of Search: None
• US Class Current: 623/23.56
• CPC Class Codes: A61F 2/30 Joints
• CPC Class Codes: A61F 2002/30024 differing in coefficient of friction
• CPC Class Codes: A61F 2002/30026 differing in wear resistance
• CPC Class Codes: A61L 27/306 Other specific inorganic materials not covered by A61L27/303 - A61L27/32
• CPC Class Codes: C22C 45/10 with molybdenum, tungsten, niobium, tantalum, titanium, or zirconium or Hf as the major constituent
• CPC Class Codes: C23C 30/00 Coating with metallic material characterised only by the composition of the metallic material, i.e. not characterised by the coating process C23C26/00, C23C28/00 take precedence
• CPC Class Codes: C23C 8/02 Pretreatment of the material to be coated C23C8/04 takes precedence
• CPC Class Codes: C23C 8/10 Oxidising

Abstract

A coating of blue-black or black zirconium of uniform and controlled thickness on a zirconium or zirconium alloy material is accomplished through the treatment of an amorphous zirconium or zirconium alloy substrate, which may have an altered surface roughness. The treatment of amorphous zirconium or zirconium alloy substrates includes oxidation of the substrates. A zirconium coating of uniform and controlled thickness is especially useful in various applications because the uniformly thick zirconium surface of controlled depth provide a barrier against implant corrosion caused by ionization of the metal substrates.

Claims

1. A substrate comprising:

a zirconium or a zirconium alloy having an amorphous structure; and

a surface layer of blue-black or black zirconium oxide on at least a portion of said zirconium or a zirconium alloy,

wherein said surface layer has a substantially uniform thickness.

2. The substrate of claim 1, wherein a portion of said zirconium or zirconium alloy further comprises an altered surface roughness.

3. The substrate of claim 2, wherein said altered surface roughness comprises a surface roughness (Ra) in the range of about 3 microinches to about 25 microinches.

4. The substrate of claim 3, wherein said altered surface roughness comprises a surface roughness (Ra) in the range of about 3.5 microinches to about 7 microinches.

5. The substrate of claim 1, wherein said surface layer has a thickness of up to about 20 microns.

6. The substrate of claim 1, wherein said surface layer has a thickness of up to about 10 microns.

7. The substrate of claim 1, wherein a portion of the surface layer further comprises an irregular surface.

8. The substrate of claim 7, wherein said irregular surface comprises zirconium or zirconium alloy beads attached to the outer surface of the substrate, and wherein at least a portion of the surface of the beads is oxidized to said blue-black or black zirconium oxide surface layer.

9. The substrate of claim 7, wherein said irregular surface comprises a chemically etched surface.

10. The substrate of claim 7, wherein said irregular surface comprises a plasma spray-deposited surface.

11. The substrate of claim 7, wherein said irregular surface comprises a sintered surface.

12. The substrate of claim 7, wherein said irregular surface comprises zirconium or zirconium alloy wire mesh connected to the outer surface of the substrate, wherein at least a portion of the surface of the mesh is oxidized to said blue-black or black zirconium oxide surface layer.

13. The substrate of claim 1, wherein said surface layer of zirconium oxide has a thickness in the range of about 3 microns to about 7 microns.

14. The substrate of claim 1, wherein said surface layer of zirconium oxide comprises a polished surface.

15. The substrate of claim 1, wherein said surface layer comprises oxidized zirconium.

16. The substrate of claim 15, wherein said oxidized surface layer is formed by oxidation of said zirconium or zirconium alloy.

17. The substrate of claim 16, wherein said oxidation of the zirconium or zirconium alloy comprises furnace oxidation with oxygen at a temperature in the range of about 900 degrees F. to 1300 degrees F.

18. The substrate of claim 15, wherein a portion of said zirconium or zirconium alloy further comprises an altered surface roughness prior to said oxidation.

19. The substrate of claim 18, wherein said altered surface roughness is formed by subjecting said portion of zirconium or zirconium alloy to an abrasive surface preparation process selected from the group consisting of grinding, buffing, mass finishing, vibratory finishing, and a combination thereof.

20. The substrate of claim 1, wherein said oxidation of the zirconium or zirconium alloy comprises salt-bath oxidation with at least one salt selected from the group consisting of chlorides, nitrates, cyanides, and a combination thereof.