US5202088A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ferritic heat-resisting cast steel and a process for making the same
Assignee: Toyota Motor Corp
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Filing: 1991-12-27
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Granted: 1993-04-13
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Expires: 2011-12-27
Abstract
Abstract Ferritic heat-resisting cast steel, which intends to highten the applicability for use of the exhaust manifold of a vehicle engine without losing oxidation resistance, machinability and structural stability, containing, on a weight basis, 0.05 to 0.5% C, 1.0 to 2.0% Si, less than 0.6% Mn, less than 0.04% P, less than 0.04% S, less than 0.5% Ni, 10 to 20% Cr, 0.1 to 1.0% V, 0.5 to 1.0% Nb, 0.08 to 0.50% Mo, less than 0.01% W and 0.01 to 0.2% Ce, the balance of its composition being iron. Alternatively, it may contain 0.1 to 1.5% Mn and 0.01 to 0.2% S, and may further contain 0.01 to 0.2% Te and/or 0.01 to 0.3% Al. Further, it may contain 0.1 to 5.0% Co and/or 0.1 to 5.0% Ti. The cast steel is annealed at a temperature of 850° C. to 1000° C. for one to five hours.
Inventors
- 👤 Yoshikazu Genma
- 👤 Shinji Katou
- 👤 Masami Suzuki
- 👤 Shinya Mizuno
- 👤 Tsutomu Sekiguchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 22:07
CPC Classifications
C; C22; C22C; C22C38/00; C22C38/18; C22C38/24; C22C38/22; C22C38/26
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
66 words
A ferritic heat-resisting cast steel consisting essentially of: on a weight basis, 0.05 to 0.5% C, 1.0 to 2.0% Si, less than 0.6% Mn, less than 0.04% P, less than 0.04% S, less than 0.5% Ni, 10 to 20% Cr, 0.1 to 1.0% V, 0.5 to 1.0% Nb, 0.08 to 0.50% Mo, less than 0.01 W and 0.01 to 0.2% Ce, the balance thereof being iron.
Claim 2
Dependent Claim
66 words
A ferritic heat-resisting cast steel consisting essentially of: on a weight basis, 0.05 to 0.5% C, 1.0 to 2.0% Si, less than 0.6% Mn, less than 0.04% P, less than 0.04% S, less than 0.5% Ni, 10 to 20% Cr, 0.1 to 1.0% V, 0.5 to 1.0% Nb, 0.08 to 0.50% Mo, less than 0.01 W and 0.01 to 0.2% Ce, the balance thereof being iron.
Claim 3
Dependent Claim
26 words
A cast steel as set forth in claim 1, further consisting essentially of 0.1 to 5.0 wt. % Co and/or 0.1 to 5.0 wt % Ti.
Claim 4
Dependent Claim
19 words
A cast steel as set forth in claim 2, further consisting essentially of 0.01 to 1.00 wt % Al.
Claim 5
Dependent Claim
87 words
A ferritic heat-resisting cast steel consisting essentially of, on a weight basis, 0.05 to 0.5% C, 1.0 to 2.0% Si, 0.1 to 1.5% Mn, less than 0.04% P, 0.01 to 0.20% S, less than 0.5% Ni, 10 to 20% Cr, 0.1 to 1.0% V, 0.5 to 1.0% Nb, 0.08 to 0.50% Mo, less than 0.01 W and 0.01 to 0.2% Ce, wherein said steel satisfies the relation S≦Mn and is annealed at 850° to 1000° C. for the period of time of from 1 to 5 hours.
Claim 6
Dependent Claim
87 words
A ferritic heat-resisting cast steel consisting essentially of, on a weight basis, 0.05 to 0.5% C, 1.0 to 2.0% Si, 0.1 to 1.5% Mn, less than 0.04% P, 0.01 to 0.20% S, less than 0.5% Ni, 10 to 20% Cr, 0.1 to 1.0% V, 0.5 to 1.0% Nb, 0.08 to 0.50% Mo, less than 0.01 W and 0.01 to 0.2% Ce, wherein said steel satisfies the relation S≦Mn and is annealed at 850° to 1000° C. for the period of time of from 1 to 5 hours.
Claim 7
Dependent Claim
26 words
A cast steel as set forth in claim 4, further consisting essentially of 0.01 to 0.2 wt. % Te and/or 0.01 to 0.30 wt. % Al.
Claim 8
Dependent Claim
24 words
A ferritic heat-resisting cast steel as set forth in claim 4, further consisting essentially of 0.1 to 5.0% Co and/or 0.1 to 5.0% Ti.
Claim 9
Dependent Claim
19 words
A cast steel as set forth in claim 6, further consisting essentially of 0.01 to 1.00 wt. % Al.
Claim 10
Dependent Claim
42 words
A process for making ferritic heat-resisting cast steel which comprises casting steel having the composition as set forth in claim 1 and annealing at a temperature of 850° to 1000° C. for a period of time of from 1 to 5 hours.
Claim 11
Dependent Claim
42 words
A process for making ferritic heat-resisting cast steel which comprises casting steel having the composition as set forth in claim 4 and annealing at a temperature of 850° to 1000° C. for a period of time of from 1 to 5 hours.
References Cited (Backward Citations)
JPS5773170A
Cited
JPH01159354A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-04-12 | 1996-10-12 | 1997-04-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-04-12 | 2000-10-12 | 2001-04-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-04-12 | 2004-10-12 | 2005-04-13 | $7700.00 | Window Closed / Lapsed |