US3765954A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Surface-hardened titanium and titanium alloys and method of processing same
Assignee: Kobe Steel Ltd
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Filing: 1971-03-22
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Granted: 1973-10-16
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Expires: 1991-03-22
Abstract
Abstract Surface-hardened pure titanium or titanium-base alloys having a coating of a substitution type metal, which metal is characterized by a larger diffusion constant than titanium, is more readily nitrided than titanium, has a higher density than the base metal, is rich in stable beta phase, and which has a Vickers hardness of above 400. This hardened titanium or titanium-base alloy is produced by a method of hardening the surface of pure titanium or a titanium-base alloy which includes the steps of coating a substitution type metal of the abovementioned type and heating the coated metal in a nitrogencontaining atmosphere.
Inventors
- 👤 S Tokuda
- 👤 H Kawahara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 22:24
CPC Classifications
C; C23; C23C; C23C12/00; Y; Y10; Y10S; Y10S428/00; Y10S428/922; Y10S428/923; Y10S428/924; Y10S428/926; Y10S428/9335; Y10S428/941; Y10T; Y10T428/00; Y10T428/12; Y10T428/12458; Y10T428/12493; Y10T428/12771; Y10T428/12778; Y10T428/12806
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
34 words
A surface-hardened titanium-base alloy as set forth in claim 1, wherein said alloy is of the Ti-Al-V type Ti-Al-Sn type, Ti-Al-Cr-Fe type, Ti-Al-Mo-V type, Ti-Al-V-Sn type, Ti-V-Cr-Al type, Ti-Mo-Zr-Sn type, or the Ti-Al-Sn-Zr-Mo-Si type.
Claim 2
Independent Claim
119 words
A method of hardening the surface of pure titanium or a titanium base alloy metal, which comprises coating onto said base metal a substitutional metal, selected from the group consisting of Fe, Ni, Cu, in sufficient thickness to provide a surface hardened layer of at least 100 microns heating said coated metal in a nitrogen atmosphere at a temperature of 750* - 1,050*C. for a period of 10 - 100 hours, whereby the coated metal is nitrided and is diffused into the base metal and simultaneously nitrogen is diffused into the base metal whereby a hardened layer which is richer in stable beta phase than the base metal and which has a Vicker''s hardness of above 400 is obtained.
Claim 3
Dependent Claim
20 words
A method as set forth in claim 3, wherein said coating step is plating, depositing, welding, discharge coating, or painting.
Claim 4
Dependent Claim
14 words
A method as set forth in claim 3, further comprising the step of aging.
Claim 5
Dependent Claim
21 words
A method as set forth in claim 3, wherein said aging step is conducted at a temperature of 400* - 60*C.
References Cited (Backward Citations)
US1944179A
Cited
US1936294A
Cited
US1929252A
Cited
US2645575A
Cited
US2858600A
Cited
US2950233A
Cited
US2864731A
Cited
US3471342A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-10-15 | 1977-04-16 | 1977-10-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-15 | 1981-04-16 | 1981-10-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-15 | 1985-04-16 | 1985-10-16 | $7700.00 | Window Closed / Lapsed |