US2887421A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of producing castings having high mechanical properties
Assignee: Renault SA
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Filing: 1955-12-27
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Granted: 1959-05-19
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Expires: 1975-12-27
Abstract
No abstract record available.
Inventors
- 👤 Peras Lucien
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 10:53
CPC Classifications
C; C22; C22C; C22C37/00; C22C37/04
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
85 words
IN A PROCESS OF THERMALLY TREATING WHITE CASTINGS TO PRODUCE MALLEABLE IRON WITH ANNEALED SPHEROIDAL GRAPHITE THEREFROM, SAID CASTINGS CONTAINING 0.2 TO 0.3% SULFUR AND 0.002 TO 0.15 MANGANESE WITH THE RATIO S/MN BEING GREATER THAN 1, SAID PROCESS COMPRISING THE STEPS OF HEATING SAID CASTINGS AND DIRECTLY QUENCHING TO IMPART A MARTENSITIC STRUCTURE TO THE METAL, HEATING AT 300* TO 700* C. FOR 1 TO 4 HOURS AND GRHAPHITIZING BY HEATING FOR 3 TO 8 HOURS AT A TEMPERATURE OF 850* TO 900* C.
References Cited (Backward Citations)
US1542440A
Cited
US2185894A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-05-18 | 1962-11-17 | 1963-05-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-05-18 | 1966-11-17 | 1967-05-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-05-18 | 1970-11-17 | 1971-05-19 | $7700.00 | Window Closed / Lapsed |