US4900398A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Chemical milling of titanium
Assignee: Rolls Royce Corp
•
Filing: 1989-06-19
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Granted: 1990-02-13
•
Expires: 2009-06-19
Abstract
Abstract Process for chemically milling titanium using an aqueous milling solution consisting essentially of (by weight) about 1% to 5% HF, about 1.5% to 4% chlorate ion and optionally up to about 20% of an acid selected from the group consisting of H 2 SO 4 , HCl and HNO 3 .
Inventors
- 👤 Yu-Lin Chen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 05:25
CPC Classifications
C; C23; C23F; C23F1/00; C23F1/10; C23F1/14; C23F1/16; C23F1/26
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
84 words
In the method of chemically milling titanium comprising the principle steps of contacting a surface of said titanium to be milled with aqueous milling solution for a time sufficient to corrode said surface a predetermined amount, the improvement wherein said solution, by weight, consists essentially of 1% to about 5% hydrofluoric acid, about 1.5% to about 4% chlorate ion, and, optionally, up to about 20% of an acid selected from the group consisting of H 2 SO 4 , HCl, and HNO 3 .
Claim 2
Dependent Claim
84 words
In the method of chemically milling titanium comprising the principle steps of contacting a surface of said titanium to be milled with aqueous milling solution for a time sufficient to corrode said surface a predetermined amount, the improvement wherein said solution, by weight, consists essentially of 1% to about 5% hydrofluoric acid, about 1.5% to about 4% chlorate ion, and, optionally, up to about 20% of an acid selected from the group consisting of H 2 SO 4 , HCl, and HNO 3 .
Claim 3
Dependent Claim
33 words
The method according to claim 1 wherein said acid is H 2 SO 4 and said chlorate ion is provided by a salt selected from the group consisting of sodium and potassium chlorate.
Claim 4
Dependent Claim
25 words
The method according to claim 2 wherein said solution consists essentially of about 2% hydrofluoric acid, about 4% sulfuric acid, and about 3.5% sodium chlorate.
Claim 5
Dependent Claim
18 words
The method according to claim 3 wherein said milling is performed at temperatures up to about 200° F.
Claim 6
Dependent Claim
20 words
The method according to claim 4 wherein said milling is performed at temperatures between about 100° F. and 125° F.
References Cited (Backward Citations)
US2847371A
Cited
US2942954A
Cited
US2827402A
Cited
US2856275A
Cited
US2981609A
Cited
US3007780A
Cited
US3082137A
Cited
US3514407A
Cited
US3666580A
Cited
US3844859A
Cited
US3788914A
Cited
US3944496A
Cited
US4116755A
Cited
US4220706A
Cited
US4314876A
Cited
US4416739A
Cited
US4345969A
Cited
US4540465A
Cited
US4704126A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-02-12 | 1993-08-14 | 1994-02-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-02-12 | 1997-08-14 | 1998-02-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-02-12 | 2001-08-14 | 2002-02-13 | $7700.00 | Window Closed / Lapsed |