US3799765A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Free-machining stainless steel
Assignee: Armco Inc
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Filing: 1972-02-29
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Granted: 1974-03-26
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Expires: 1992-02-29
Abstract
Abstract STRAIGHT-CHROMIUM STEEL IS CHARACTERIZED BY A COMBINATION OF READY MACHINALBILITY AND GOOD CORROSIONRESISTANCE. IN ADDITION TO CHROMIUM OF ABOUT 11.5% TO 18%, THE STEEL CONTAINS CRITICAL AMOUNTS OF THE THREE INGREDIENTS PHOSPHORUS, SULPHUR AND ZIRCONIUM, NAMELY, ABOUT 0.04% TO 0.12% PHOSPHORUS, ABOUT 0.20% TO 0.50% SULPHUR AND ABOUT 0.10% TO 0.40% ZIRCONIUM. CONVENIENTLY, THE STEEL IS MELTED IN THE ELECTRIC ARC FURNACE, AND FOR BEST RESULTS, TEEMING IS EFFECTED IN A PROTECTIVE ATMOSPHERE.
Inventors
- 👤 W Clarke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 16:02
CPC Classifications
C; C22; C22C; C22C38/00; C22C38/18; C22C38/28
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-03-25 | 1977-09-24 | 1978-03-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-03-25 | 1981-09-24 | 1982-03-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-03-25 | 1985-09-24 | 1986-03-26 | $7700.00 | Window Closed / Lapsed |