Patent US4140527A successfully refreshed from Google Patents.
US4140527A
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Nitrogen containing powder metallurgical tool steel
Assignee: Kobe Steel Ltd
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Filing: 1977-05-23
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Granted: 1979-02-20
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Expires: 1997-05-23
Abstract
Abstract A nitrogen containing powder metallurgical tool steel comprising at least 0.40% N, 1.6 - 15% V, C in an amount satisfying the relationship of 0.2 + 0.2 V(%)</=(C + N)<0.5 + 0.
Inventors
- 👤 Nobuyasu Kawai
- 👤 Katuhiko Honma
- 👤 Hirofumi Fujimoto
- 👤 Hiroshi Takigawa
- 👤 Tsuneo Tatsuno
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 17:32
CPC Classifications
C; C22; C22C; C22C33/00; C22C33/02; C22C33/0257; C22C33/0278; C22C33/0292
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
114 words
A nitrogen containing high speed tool steel produced by hot isostatic pressing by the powder metallurgical process which comprises; at least 0.40%N, 1.6 - 15% V, C in an amount satisfying the relationship of 0.2 + 0.2 V(%) ≦ (C + N) <0.5 + 0.2 V(%), at least one element selected from the group consisting of up to 15% Cr, up to 10% Mo, up to 20% W and up to 15% Co; optionally at least one element selected from the group consisting of up to 3% Ni, up to 1% Mn, up to 1% Si, up to 2% Zr, up to 5% Nb and up to 1% B; and with the balance iron.
Claim 2
Dependent Claim
114 words
A nitrogen containing high speed tool steel produced by hot isostatic pressing by the powder metallurgical process which comprises; at least 0.40%N, 1.6 - 15% V, C in an amount satisfying the relationship of 0.2 + 0.2 V(%) ≦ (C + N) <0.5 + 0.2 V(%), at least one element selected from the group consisting of up to 15% Cr, up to 10% Mo, up to 20% W and up to 15% Co; optionally at least one element selected from the group consisting of up to 3% Ni, up to 1% Mn, up to 1% Si, up to 2% Zr, up to 5% Nb and up to 1% B; and with the balance iron.
Claim 3
Dependent Claim
20 words
The nitrogen containing powder metallurgical tool steel as set forth in claim 1, wherein at least 0.45% N is contained.
Claim 4
Dependent Claim
42 words
The nitrogen containing powder metallurgical tool steel as set forth in claim 1, wherein said steel further comprises at least one element selected from the group consisting of up to 3% Ni, up to 1% Mn and up to 1;l % Si.
Claim 5
Dependent Claim
40 words
The nitrogen containing powder metallurgical steel as set forth in claim 1, wherein said steel further comprises at least one element selected from the group consiting of up to 2% Zr, up to 5% Nb and up to 1% B.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-02-19 | 1982-08-21 | 1983-02-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-02-19 | 1986-08-21 | 1987-02-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-02-19 | 1990-08-21 | 1991-02-20 | $7700.00 | Window Closed / Lapsed |