US3880585A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of inhibiting stress cracking
Assignee: Individual
•
Filing: 1972-05-18
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Granted: 1975-04-29
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Expires: 1992-05-18
Abstract
Abstract A method of inhibiting stress cracking in stainless steel articles exposed to a chloride-ion containing fluid environment in which the surface of the stainless steel article is contacted with a trace amount of an inorganic metal salt or with the metal corresponding to the cation of the salt so as to enlarge the anodic areas on the surface and increase the uniformity of the electrical potential of the surface thereby eliminating concentrated non-uniform attack on the surface and attendant cracking.
Inventors
- 👤 Daniel N Hess
- 👤 Ramon A Bannister
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 21:41
CPC Classifications
C; C23; C23F; C23F11/00; C23F11/08; C23F11/18; C23F11/181
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
42 words
A METHOD OF INHIBITING STRESS CRACKING OF STAINLESS STEEL IN A CHLORIDE-ION FLUID ENVIRONMENT COMPRISING, CONTACTING A STAINLESS STEEL SURFACE IN A CHLORIDE-ION CONTAINING FLUID ENVIRONMENT WITH MERCURIC NITRATE IN AN EFFECTIVE AMOUNT OF INHIBIT STESS CRACKING OF SAID STAINLESS STEEL SURFACE.
Claim 2
Independent Claim
42 words
A METHOD OF INHIBITING STRESS CRACKING OF STAINLESS STEEL IN A CHLORIDE-ION FLUID ENVIRONMENT COMPRISING, CONTACTING A STAINLESS STEEL SURFACE IN A CHLORIDE-ION CONTAINING FLUID ENVIRONMENT WITH MERCURIC NITRATE IN AN EFFECTIVE AMOUNT OF INHIBIT STESS CRACKING OF SAID STAINLESS STEEL SURFACE.
Claim 3
Dependent Claim
40 words
A method in accordance with claim 1 comprising the further step of adjusting the pH of said chloride ion-containing fluid by the addition thereto of from 0.001 to 0.008 parts per million of said chloride ion-containing fluid of nitric acid.
Claim 4
Dependent Claim
25 words
A method in accordance with claim 1 wherein said contacting step is carried out by adding said mercuric nitrate to said chloride-ion containing fluid environment.
Claim 5
Dependent Claim
22 words
A method in accordance with claim 3 wherein said chloride-ion containing fluid enviroment comprises an aqueous solution containing a quantity of chloride-ions.
Claim 6
Dependent Claim
29 words
A method in accordance with claim 4 wherein the quantity of mercuric Nitrate added is within the range of 2-1000 parts per million of said chloride-ion containing fluid enviroment.
References Cited (Backward Citations)
US2945794A
Cited
US2837474A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-04-28 | 1978-10-28 | 1979-04-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-28 | 1982-10-28 | 1983-04-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-28 | 1986-10-28 | 1987-04-29 | $7700.00 | Window Closed / Lapsed |