US3943010A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for producing austenitic ferrous alloys
Assignee: Allegheny Ludlum Corp
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Filing: 1974-06-12
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Granted: 1976-03-09
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Expires: 1994-06-12
Abstract
Abstract There is disclosed a method for producing austenitic ferrous alloys containing from 21-45% manganese and from 10-30% chromium by exposing the alloys in solid form to nitrogen or nitrogen compounds at a temperature of at least 1700°F for a time period sufficient to raise the nitrogen content of at least the surface of the alloy to at least 0.85%.
Inventors
- 👤 Albert G. Hartline, III
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 11:31
CPC Classifications
C; C22; C22C; C22C38/00; C22C38/18; C22C38/38; C21; C21D; C21D6/00; C23; C23C; C23C8/00; C23C8/06; C23C8/08; C23C8/24; C23C8/26
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
59 words
An article of manufacture comprising a solid ferrous alloy consisting essentially of from about 21-45% manganese, from about 10-30% chromium, balance essentially iron, and having at its surface from about 0.85-3% nitrogen with a lesser nitrogen content in its interior than at its surface, said article having an austenitic surface and a two phase interior of austenitic and ferrite.
Claim 2
Dependent Claim
59 words
An article of manufacture comprising a solid ferrous alloy consisting essentially of from about 21-45% manganese, from about 10-30% chromium, balance essentially iron, and having at its surface from about 0.85-3% nitrogen with a lesser nitrogen content in its interior than at its surface, said article having an austenitic surface and a two phase interior of austenitic and ferrite.
Claim 3
Dependent Claim
45 words
An article according to claim 1 wherein said alloy additionally contains at least one metal from the group consisting of 1-5% molybdenum, 1-4% nickel and 1-3% copper, and wherein said alloy, when two or more said metals are present, does not exceed 5% total thereof.
Claim 4
Dependent Claim
46 words
An article of manufacture comprising a solid ferrous alloy consisting essentially of from about 21-45% manganese, from about 10-30% chromium, balance essentially iron, and at its surface from about 0.85-3% nitrogen -- said article having an austenitic surface and a two-phase interior comprising austenite and ferrite.
Claim 5
Dependent Claim
46 words
An article of manufacture comprising a solid ferrous alloy consisting essentially of from about 21-45% manganese, from about 10-30% chromium, balance essentially iron, and at its surface from about 0.85-3% nitrogen -- said article having an austenitic surface and a two-phase interior comprising austenite and ferrite.
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) | 1979-03-09 | 1979-09-08 | 1980-03-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-03-09 | 1983-09-08 | 1984-03-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-03-09 | 1987-09-08 | 1988-03-09 | $7700.00 | Window Closed / Lapsed |