US5427631A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Prosthetic articles made of surface conversion nitrided titanium or titanium alloys
Assignee: Ytbolaget I Uppsala AB
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Filing: 1994-03-30
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Granted: 1995-06-27
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Expires: 2014-03-30
Abstract
Abstract Objects of titanium or titanium alloys having the surface converted to a hard and wear-resistant nitride layer with good adhesion, which is distributed uniformly and also provides internal capillaries. The objects are produced by being treated in a vacuum furnace with an atmosphere of pure nitrogen gas at a temperature of 650°-1000° C. and at a pressure below atmospheric pressure. The thickness of the nitride layer can be controlled by controlling the treatment time and temperature.
Inventors
- 👤 Erik Johansson
- 👤 Helena Westberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 23:20
CPC Classifications
C; C23; C23C; C23C8/00; C23C8/06; C23C8/08; C23C8/24; A; A61; A61F; A61F2/00; A61F2/02; A61F2/30; A61F2/30767; A61F2/3094; A61F2002/30922; A61F2310/00; A61F2310/00005; A61F2310/00011; A61F2310/00023; A61F2310/00389; A61F2310/00592; A61F2310/00856; A61F2310/0088; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12493; Y10T428/12771; Y10T428/12806
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
61 words
Articles comprising joint prostheses, prothesis shafts, wear-parts for prosthesis shafts, hip and knee joints, valve parts or pump cylinders formed of titanium and titanium alloys and having a surface conversion layer consisting of an integral continuous uniformly distributed, hard, wear-resistant and pure titanium nitride layer of between 0.5 and 10 μm having a hardness of at least 2000 hV 0 .05.
Claim 2
Dependent Claim
61 words
Articles comprising joint prostheses, prothesis shafts, wear-parts for prosthesis shafts, hip and knee joints, valve parts or pump cylinders formed of titanium and titanium alloys and having a surface conversion layer consisting of an integral continuous uniformly distributed, hard, wear-resistant and pure titanium nitride layer of between 0.5 and 10 μm having a hardness of at least 2000 hV 0 .05.
Claim 3
Dependent Claim
18 words
Articles as claimed in claim 1, wherein the pure titanium nitride layer is between 2 and 4 μm.
Claim 4
Dependent Claim
20 words
Articles as claimed in claim 1, wherein the surface is finished to high surface fineness using a chemo-mechanical polishing method.
Claim 5
Dependent Claim
20 words
Articles as claimed in claim 2, wherein the surface is finished to high surface fineness using a chemo-mechanical polishing method.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-06-26 | 1998-12-26 | 1999-06-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-06-26 | 2002-12-26 | 2003-06-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-06-26 | 2006-12-26 | 2007-06-27 | $7700.00 | Window Closed / Lapsed |