US5415704A
Expired / Lapsed
US
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Surface hardened biocompatible metallic medical implants
Assignee: Smith and Nephew Inc
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Filing: 1993-09-13
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Granted: 1995-05-16
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Expires: 2013-09-13
Abstract
Abstract This invention provides surface hardened, abrasion resistant high strength, biocompatible metal medical implants, in particular, titanium alloy implants which do not include any elements which have been shown or suggested as having short term or long term potential adverse effect from a standpoint of biocompatibility. Further, the invention provides methods of strengthening and hardening the surfaces of other titanium, zirconium, and cobalt-based alloy implants with small concentrations of a metal solute such as zirconium, yttrium, tantalum, aluminum, silicon, chromium, or thorium via internal oxidation or nitridation. Alternatively, nitrogen, oxygen, or carbon can be diffused directly into the surface of the implants by interstitial hardening to further increase the surface abrasion resistance of these internally oxidized or internally nitridized implant metal or metal alloys.
Inventors
- 👤 James A. Davidson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 01:38
CPC Classifications
A; A61; A61L; A61L27/00; A61L27/28; A61L27/30; A61L27/306; A61F; A61F2/00; A61F2/02; A61F2/30; A61F2/30767; A61L27/02; A61L27/04; A61L27/045; A61L27/06; A61F2002/30922; A61F2310/00; A61F2310/00005; A61F2310/00011; A61F2310/00017; A61F2310/00023; A61F2310/00029; A61F2310/00035; A61F2310/00089; A61F2310/00389; A61F2310/00592; A61F2310/00598; A61F2310/00856
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
108 words
A surface hardened metallic medical implant, the implant comprising: a surface hardened metallic alloy implant body with surface hardness greater than about 40 Rockwell C, the alloy comprising metallic elements and the hardened surface produced by a process comprising: (i) selecting a metallic alloy containing less than about 2 wt. % of a metal solute more readily oxidizable than and different than other elements of the metallic alloy implant body; (ii) hardening the surface of the implant body by internal oxidation of a substantial proportion of the more readily oxidizable solute at the surface of the implant while maintaining a metallic luster on the surface of the implant.
Claim 2
Dependent Claim
108 words
A surface hardened metallic medical implant, the implant comprising: a surface hardened metallic alloy implant body with surface hardness greater than about 40 Rockwell C, the alloy comprising metallic elements and the hardened surface produced by a process comprising: (i) selecting a metallic alloy containing less than about 2 wt. % of a metal solute more readily oxidizable than and different than other elements of the metallic alloy implant body; (ii) hardening the surface of the implant body by internal oxidation of a substantial proportion of the more readily oxidizable solute at the surface of the implant while maintaining a metallic luster on the surface of the implant.
Claim 3
Dependent Claim
62 words
The hardened metallic medical implant of claim 1, wherein the metallic alloy of the implant body is selected from the group of alloys and metals consisting of Ti-6Al-4V, Ti--Mo, Ti--Al--Nb, Ti--Fe, Ti--V, Zr, Zr--Nb, Ti--Nb, Ti--Nb--Zr, Co--Cr--Mo, and Fe--Cr--Ni--Mo; and the more readily oxidizable metal solute is selected from the group consisting of tantalum, yttrium, hafnium, thorium, zirconium, chromium, niobium, and aluminum.
Claim 4
Dependent Claim
49 words
The hardened metallic medical implant of claim 1, wherein the implant body comprises a metal alloy having a composition of about 84 wt. % titanium, and about 15 wt. % niobium; and the metal solute is selected from the group consisting of tantalum, yttrium, zirconium, hafnium, chromium, and aluminum.
Claim 5
Dependent Claim
49 words
The hardened metallic medical implant of claim 1, wherein the metallic alloy implant body comprises about 74 wt. % titanium, about 13 wt. % niobium, and about 13 wt. % zirconium; and the metal solute is selected from the group consisting of hafnium, chromium, tantalum, yttrium, thorium, and aluminum.
Claim 6
Dependent Claim
23 words
The surface hardened metallic medical implant of claim 1, wherein the metallic alloy implant body comprises Ti-6Al-4V; and the metal solute is tantalum.
Claim 7
Dependent Claim
33 words
The surface hardened metallic medical implant of claim 1, wherein the metallic alloy implant body comprises Co--Cr--Mo alloy and the metal solute is selected from the group consisting of tantalum, aluminum, and yttrium.
Claim 8
Dependent Claim
33 words
The surface hardened metallic medical implant of claim 1, wherein the metallic alloy implant body comprises Fe--Cr--Ni--Mo alloy and the metal solute is selected from the group consisting of tantalum, aluminum, and yttrium.
Claim 9
Dependent Claim
39 words
The surface hardened metallic medical implant of claim 2, wherein the implant body has been further hardened by diffusion into the metallic alloy of the implant of an element selected from the group consisting of nitrogen, oxygen, and carbon.
Claim 10
Dependent Claim
116 words
A surface hardened metallic medical implant, the implant having a metallic alloy body with a surface, the body comprising: a metallic alloy, and less than about 2 wt. % of a metal solute that is more oxidizable than metallic components of the metallic alloy body, a substantial proportion of the metal solute at a depth of less than about 200 microns beneath the surface of the implant body being oxidized to strengthen and harden the surface of the implant to a hardness of about 40 Rockwell C, the solute being oxidized by a process comprising internally oxidizing solute near the surface of the implant body while maintaining a metallic luster on the surface of the implant.
Claim 11
Dependent Claim
116 words
A surface hardened metallic medical implant, the implant having a metallic alloy body with a surface, the body comprising: a metallic alloy, and less than about 2 wt. % of a metal solute that is more oxidizable than metallic components of the metallic alloy body, a substantial proportion of the metal solute at a depth of less than about 200 microns beneath the surface of the implant body being oxidized to strengthen and harden the surface of the implant to a hardness of about 40 Rockwell C, the solute being oxidized by a process comprising internally oxidizing solute near the surface of the implant body while maintaining a metallic luster on the surface of the implant.
Claim 12
Dependent Claim
15 words
The surface hardened metallic medical implant of claim 9, wherein the body comprises Co--Cr--Mo alloy.
Claim 13
Dependent Claim
14 words
The surface hardened metallic medical implant of claim 9, wherein the body comprises Ti-6Al-4V.
Claim 14
Dependent Claim
15 words
The surface hardened metallic medical implant of claim 9, wherein the body comprises Fe--Cr--Ni--Mo alloy.
Claim 15
Dependent Claim
24 words
The surface hardened metallic medical implant of claim 10, wherein the metal solute is selected from the group consisting of tantalum, aluminum, and yttrium.
Claim 16
Dependent Claim
15 words
The surface hardened metallic medical implant of claim 11, wherein the metal solute is tantalum.
Claim 17
Dependent Claim
100 words
A surface hardened metallic medical implant, the implant comprising: a surface hardened cobalt-chromium-molybdenum implant body with surface hardness greater than about 40 Rockwell C, the alloy comprising a hardened surface produced by a process comprising: (1) selecting a cobalt-chromium-molybdenum alloy containing from about 1 to about 2 wt. % tantalum, the tantalum being more internally oxidizable than other elements of the cobalt-chromium-molybdenum alloy implant body; (2) hardening the surface of the implant body by internal oxidation of a substantial proportion of the tantalum at the surface of the implant while maintaining a metallic luster on the surface of the implant.
Claim 18
Dependent Claim
100 words
A surface hardened metallic medical implant, the implant comprising: a surface hardened cobalt-chromium-molybdenum implant body with surface hardness greater than about 40 Rockwell C, the alloy comprising a hardened surface produced by a process comprising: (1) selecting a cobalt-chromium-molybdenum alloy containing from about 1 to about 2 wt. % tantalum, the tantalum being more internally oxidizable than other elements of the cobalt-chromium-molybdenum alloy implant body; (2) hardening the surface of the implant body by internal oxidation of a substantial proportion of the tantalum at the surface of the implant while maintaining a metallic luster on the surface of the implant.
Claim 19
Dependent Claim
94 words
A surface hardened metallic medical implant, the implant having a metallic alloy body with a surface, the body comprising: a cobalt-chromium-molybdenum alloy, and from about 1 to about 2 wt. % of tantalum as a metal solute, a substantial proportion of the tantalum at a depth of less than about 200 microns beneath surfaces of the implant body being oxidized to strengthen and harden the surface to a hardness of about 40 Rockwell C, the tantalum solute being oxidized by a process comprising internally oxidizing said solute near the surface of the implant body.
Claim 20
Dependent Claim
94 words
A surface hardened metallic medical implant, the implant having a metallic alloy body with a surface, the body comprising: a cobalt-chromium-molybdenum alloy, and from about 1 to about 2 wt. % of tantalum as a metal solute, a substantial proportion of the tantalum at a depth of less than about 200 microns beneath surfaces of the implant body being oxidized to strengthen and harden the surface to a hardness of about 40 Rockwell C, the tantalum solute being oxidized by a process comprising internally oxidizing said solute near the surface of the implant body.
References Cited (Backward Citations)
US3070468A
Cited
US3421890A
Cited
US3433626A
Cited
US3471342A
Cited
US3643658A
Cited
US4040129A
Cited
US4012229A
Cited
US3933484A
Cited
US4124737A
Cited
DE2811603A1
Cited
US4465524A
Cited
US4495664A
Cited
US4497771A
Cited
US4582679A
Cited
US4631082A
Cited
US4668290A
Cited
US4714468A
Cited
EP0213781A1
Cited
US4846837A
Cited
US4693760A
Cited
US4743308A
Cited
US4820324A
Cited
US4908072A
Cited
EP0359446A1
Cited
US5141574A
Cited
WO1990007016A1
Cited
US5002731A
Cited
US5145530A
Cited
US5037438A
Cited
EP0437079A1
Cited
US5169597A
Cited
EP0444280A1
Cited
US5227131A
Cited
US5178694A
Cited
US5308412A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-05-15 | 1998-11-14 | 1999-05-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-05-15 | 2002-11-14 | 2003-05-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-05-15 | 2006-11-14 | 2007-05-16 | $7700.00 | Window Closed / Lapsed |