US5178694A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Surface hardening of Ti-6Al-4V by electrolytic hydrogenation
Assignee: National Science and Technology Council
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Filing: 1992-01-08
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Granted: 1993-01-12
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Expires: 2012-01-08
Abstract
Abstract Disclosed is a process of surface hardening of Ti-6A1-4V alloy that can be performed by electrolytic charging in an acid solution, subsequent solution treatment, followed by dehydrogenation to obtain an equiaxed alpha grain in transformed beta matrix. Surface hardnesses of the processed specimens are better than that of the mill-annealed specimen. The depth of hardened layer depends on the charging time.
Inventors
- 👤 Jiann-Kuo Wu
- 👤 Tair-I Wu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:55
CPC Classifications
C; C22; C22F; C22F1/00; C22F1/16; C22F1/18; C22F1/183; C22F1/02; Y; Y10; Y10S; Y10S420/00; Y10S420/90
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
95 words
A process for surface hardening a titanium alloy, comprising: (a) cathodically charging the titanium alloy in an acid solution; (b) heating the titanium alloy to a temperature range of 500° C. to 650° C.; (c) solution treating the titanium alloy in an air furnace for producing an oxide film on the titanium alloy; (d) furnace cooling the titanium alloy to room temperature; (e) removing the oxide film of the titanium alloy; (f) dehydrogenating the titanium alloy in a vacuum furnace at 700° C. to 900° C.; (g) furnace cooling the titanium alloy to room temperature.
Claim 2
Dependent Claim
95 words
A process for surface hardening a titanium alloy, comprising: (a) cathodically charging the titanium alloy in an acid solution; (b) heating the titanium alloy to a temperature range of 500° C. to 650° C.; (c) solution treating the titanium alloy in an air furnace for producing an oxide film on the titanium alloy; (d) furnace cooling the titanium alloy to room temperature; (e) removing the oxide film of the titanium alloy; (f) dehydrogenating the titanium alloy in a vacuum furnace at 700° C. to 900° C.; (g) furnace cooling the titanium alloy to room temperature.
Claim 3
Dependent Claim
33 words
A process for surface hardening a titanium alloy as claimed in claim 1, wherein the titanium alloy is cathodically charged with a current density of about 50 mA/cm 2 at said step (a).
Claim 4
Dependent Claim
29 words
A process for surface hardening a titanium alloy as claimed in claim 1, wherein the titanium alloy is solution treated for 1 to 4 hours at said step (c).
Claim 5
Dependent Claim
35 words
A process for surface hardening a titanium alloy as claimed in claim 1, wherein the scale of the titanium alloy is removed in a solution of H 2 O 2 +HF at said step (e).
Claim 6
Dependent Claim
28 words
A process for surface hardening a titanium alloy as claimed in claim 1, wherein the titanium alloy is dehydrogenated for 1 to 4 hours at said step (f).
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) | 1996-01-12 | 1996-07-13 | 1997-01-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-01-12 | 2000-07-13 | 2001-01-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-01-12 | 2004-07-13 | 2005-01-12 | $7700.00 | Window Closed / Lapsed |