Free cutting steels
Abstract
Abstract This invention relates to free-cutting carbon steels such as S20C steel, S30C steel, S45C and S55C steel as indicated by the Japanese Industrial Standards (or steel Nos. 1020 to 1055 as indicated by the SAE Standards) containing 0.20 to 0.56 percent carbon, 0.24 to 0.33 percent silicon and 0.35 to 0.78 percent manganese. Also, this invention relates to free-cutting Ni-Cr steels, Cr-Mo steels and Cr steels containing 0.29 to 0.42 percent carbon, 0.24 to 0.33 silicon, 0.51 to 0.75 percent manganese, 0.07 to 2.89 percent nickel, 0.76 to 1.14 percent chromium and 0 to 0.26 percent molybdenum. They are characterized by the oxide inclusion contained in them, and also the calcium content and the improved free-cutting characteristic.
Inventors
- 👤 Chiaki Asada
Bibliographic Details
Claims Analysis
Total Claims: 1References Cited (Backward Citations)
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1974-12-27 | 1975-06-28 | 1975-12-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-12-27 | 1979-06-28 | 1979-12-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-12-27 | 1983-06-28 | 1983-12-28 | $7700.00 | Window Closed / Lapsed |