US3826697A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Corrosion resistant edge tools such as razor blades
Assignee: Sandvik AB
•
Filing: 1972-10-17
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Granted: 1974-07-30
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Expires: 1992-10-17
Abstract
Abstract STEELS SUITABLE FOR MAKING CORROSION-RESISTANT EDGED TOOLS (E.G., RAZOR BLADES) CONTAIN CHROMIUM AND CARBON, AND MAY CONTAIN SILICON, MANGANESE, MOLYBDENUM STEN, COPPER, COBALT, NICKEL, NIOBIUM, TANTALUM, TITANIUM VANADIUM, ZIRCONIUM, BORON, OR BERYLLIUM. THE RATIO OF CHRONUM TO CARBON IS LESS THAN 30:1: THE CARBON CONTENT IS 0.3-0.5 WT. PERCENT; AND THE CHRONIUM CONTENT IS 9.010.8 WT. PERCENT. A TOOL FORMED FROM A STEEL OF THIS CLASS HAS A HARDNESS EXCEEDING VPN 800 IN THE HARDENED CONDITION, AND A HARDNESS AFTER TEMPERING UP TO 400*C. WITHIN THE RANGE VPN 650-800.
Inventors
- 👤 J Carlen
- 👤 C Bergqvist
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 08:11
CPC Classifications
C; C22; C22C; C22C38/00; C22C38/18; C22C38/22
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) | 1977-07-29 | 1978-01-28 | 1978-07-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-07-29 | 1982-01-28 | 1982-07-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-07-29 | 1986-01-28 | 1986-07-30 | $7700.00 | Window Closed / Lapsed |