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Patent US4398966A successfully refreshed from Google Patents.
US4398966A
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Corrosion of type 304 stainless steel by laser surface treatment
Assignee: Huntington Alloys Corp
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Filing: 1982-04-28
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Granted: 1983-08-16
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Expires: 2002-04-28
Abstract
Abstract Surface treatment of stainless steel with pulsed beam from laser benefits resistance to corrosion in acid chloride media.
Inventors
- 👤 Thomas J. Kelly
- 👤 Joseph L. Nelson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 21:15
CPC Classifications
C; C21; C21D; C21D1/00; C21D1/06; C21D1/09; C21D6/00; C21D6/004
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
74 words
A process for enhancing the corrosion resistance of stainless steel comprising directing a pulsed energy beam onto a localized portion of a metal surface of stainless steel to rapidly heat the metal to at least the solid solution temperature and then chilling the thus heated metal to result in a quench rate of at least 1×10 3 °C. per second whereby the thus treated localized portion of the surface exhibits enhanced resistance to corrosion.
Claim 2
Dependent Claim
74 words
A process for enhancing the corrosion resistance of stainless steel comprising directing a pulsed energy beam onto a localized portion of a metal surface of stainless steel to rapidly heat the metal to at least the solid solution temperature and then chilling the thus heated metal to result in a quench rate of at least 1×10 3 °C. per second whereby the thus treated localized portion of the surface exhibits enhanced resistance to corrosion.
Claim 3
Dependent Claim
19 words
A process as set forth in claim 1 wherein the metal is heated to at least the melting temperature.
Claim 4
Dependent Claim
20 words
A process as set forth in claim 1 wherein the chill rate is at least 1×10 5 °C. per second.
Claim 5
Dependent Claim
27 words
A process as set forth in claim 1 wherein a pulsed laser is employed and the average operating power of the laser is at least 50 W.
Claim 6
Dependent Claim
20 words
A process as set forth in claim 1 wherein the stainless steel is of the composition known as Type 304.
Claim 7
Dependent Claim
24 words
A process as set forth in claim 1 wherein the localized portion that is heated is of about 0.254 to 1.27 mm average diameter.
Claim 8
Dependent Claim
19 words
A process as set forth in claim 1 wherein the pulse rate is 100 to 200 pulses per second.
Claim 9
Dependent Claim
17 words
A process as set forth in claim 1 wherein the laser wavelength is 0.5 to 11 microns.
Claim 10
Dependent Claim
22 words
A process as set forth in claim 1 wherein the chill rate is about 1×10 6 to 1×10 8 °C. per second.
Claim 11
Dependent Claim
27 words
A process as set forth in claim 1 wherein the travel speed of the beam relative to the metal is about 30 to 60 inches per minute.
References Cited (Backward Citations)
US2172428A
Cited
US4000011A
Cited
US3850698A
Cited
US3848104A
Cited
US4122240A
Cited
US4151014A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-08-15 | 1987-02-14 | 1987-08-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-08-15 | 1991-02-14 | 1991-08-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-08-15 | 1995-02-14 | 1995-08-16 | $7700.00 | Window Closed / Lapsed |