US2717846A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of surface hardening ferrous metals
Assignee: Individual
•
Filing: 1952-11-26
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Granted: 1955-09-13
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Expires: 1972-11-26
Abstract
No abstract record available.
Inventors
- 👤 Richard F Harvey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 21:14
CPC Classifications
C; C21; C21D; C21D1/00; C21D1/18; C21D1/19; C21D1/20; C21D8/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
106 words
A METHOD OF SURFACE HARDENING A QUENCH-HARDENABLE CAST OR WRONG FERROUS METAL COMPRISING THE STEPS OF HEATING THE SAID FERROUS METAL ABOVE ITS CRITICAL TEMPERATURE TO RENDER IT AUSTENITIC, QUENCHING THE SAID FERROUS METAL AT A RATE AT LEAST EQUAL TO ITS CRITICAL COOLING RATE TO A TEMPERATURE RANGE BETWEEN ABOUT 300* F. AND 700* F. FOR A LENGTH OF TIME INSUFFICIENT TO FORM APPRECIABLE AMOUNTS OF BAINITE AT SAID TEMPERATURES, UNIFORMLY WORKING THE SURFACE OF THE SAID FERROUS METAL IN SAID TEMPERATURE RANGE IN THE ABSENCE OF BENDING DEFLECTION TO IMPART RESIDUAL, COMPRESSIVE STRESSES THERETO, AND FINALLY COOLING THE SAID FERROUS METAL TO ROOM TEMPERATURE.
Claim 2
Independent Claim
106 words
A METHOD OF SURFACE HARDENING A QUENCH-HARDENABLE CAST OR WRONG FERROUS METAL COMPRISING THE STEPS OF HEATING THE SAID FERROUS METAL ABOVE ITS CRITICAL TEMPERATURE TO RENDER IT AUSTENITIC, QUENCHING THE SAID FERROUS METAL AT A RATE AT LEAST EQUAL TO ITS CRITICAL COOLING RATE TO A TEMPERATURE RANGE BETWEEN ABOUT 300* F. AND 700* F. FOR A LENGTH OF TIME INSUFFICIENT TO FORM APPRECIABLE AMOUNTS OF BAINITE AT SAID TEMPERATURES, UNIFORMLY WORKING THE SURFACE OF THE SAID FERROUS METAL IN SAID TEMPERATURE RANGE IN THE ABSENCE OF BENDING DEFLECTION TO IMPART RESIDUAL, COMPRESSIVE STRESSES THERETO, AND FINALLY COOLING THE SAID FERROUS METAL TO ROOM TEMPERATURE.
References Cited (Backward Citations)
US2435511A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1958-09-12 | 1959-03-14 | 1959-09-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1962-09-12 | 1963-03-14 | 1963-09-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1966-09-12 | 1967-03-14 | 1967-09-13 | $7700.00 | Window Closed / Lapsed |