Patent US4724000A successfully refreshed from Google Patents.
US4724000A
Expired / Lapsed
US
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Powdered metal valve seat insert
Assignee: Eaton Corp
•
Filing: 1986-10-29
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Granted: 1988-02-09
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Expires: 2006-10-29
Abstract
Abstract Wear resistant articles, especially valve seat inserts for internal combustion engines, are produced as sintered metal compacts comprising interspersed microzones of prealloyed austenitic stainless steel and softer ferrous metal, the microzones of austenitic stainless steel containing carbides and carbonitrides. The sintered compacts can be made by forming a green compact from prealloyed austenitic stainless steel powder atomizate blended with softer powdered ferrous metal component and powdered carbon, and sintering the green compact.
Inventors
- 👤 Jay M. Larson
- 👤 Sundaram L. Narasimhan
- 👤 David L. Bonesteel
- 👤 John N. Gilmer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 09:52
CPC Classifications
F; F01; F01L; F01L3/00; F01L3/22; C; C22; C22C; C22C33/00; C22C33/02; C22C33/0207; C22C33/0257; C22C33/0278; C22C33/0285
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
46 words
A process for making a valve seat insert which comprises the steps of: forming a green compact essentially in the shape of said insert from a blend containing prealloyed austenitic stainless steel powder atomizate, a softer ferrous metal component and powdered carbon; and sintering said compact.
Claim 2
Dependent Claim
46 words
A process for making a valve seat insert which comprises the steps of: forming a green compact essentially in the shape of said insert from a blend containing prealloyed austenitic stainless steel powder atomizate, a softer ferrous metal component and powdered carbon; and sintering said compact.
Claim 3
Dependent Claim
22 words
The process of claim 1 wherein said green compact contains about 25 to 50% by weight of said austenitic stainless steel powder.
Claim 4
Dependent Claim
10 words
The process of claim 1 wherein said carbon is graphite.
Claim 5
Dependent Claim
16 words
The process of claim 1 wherein said softer ferrous metal component is martensitic stainless steel powder.
Claim 6
Dependent Claim
44 words
The process of claim 1 wherein the overall chemical composition of the green compact is essentially as follows: ______________________________________
%
______________________________________
Carbon 1.0-2.0
Chromium 9.0-16.5
Molybdenum 0-2.0
Nickel 0.5-4.0
Silicon 0-1.8
Manganese 0.05-5.0
Copper 0-5.0
Nitrogen 0-0.50
Phosphorus 0-0.50
Sulfur 0-0.50
Iron Balance
______________________________________
Claim 7
Dependent Claim
38 words
The process of claim 1 wherein the overall chemical composition of the green compact is essentially as follows: ______________________________________
%
______________________________________
Carbon 1.0-2.0
Chromium 9.0-11.0
Molybdenum 0-2.0
Nickel 0.5-1.5
Silicon 0-0.2
Manganese 3.0-5.0
Copper 2.0-5.0
Iron Balance
______________________________________
Claim 8
Dependent Claim
11 words
The process of claim 1 wherein the sintered compact is age-hardened.
Claim 9
Dependent Claim
39 words
A process for making a sintered metal compact which consists essentially of forming a green compact from a blend comprising prealloyed austenitic stainless steel powder atomizate and a softer ferrous metal component and powdered carbon, and sintering said compact.
Claim 10
Dependent Claim
39 words
A process for making a sintered metal compact which consists essentially of forming a green compact from a blend comprising prealloyed austenitic stainless steel powder atomizate and a softer ferrous metal component and powdered carbon, and sintering said compact.
Claim 11
Dependent Claim
76 words
A powdered metal valve seat insert comprising interspersed microzones of prealloyed austenitic stainless steel and softer ferrous metal in a sintered compact, said microzones of austenitic stainless steel containing carbides and carbonitrides, and said insert made by a process comprising the steps of: forming a green compact essentially in the shape of said insert from a blend containing prealloyed austenitic stainless steel powder atomizate, a softer ferrous metal component and powdered carbon; and sintering said compact.
Claim 12
Dependent Claim
76 words
A powdered metal valve seat insert comprising interspersed microzones of prealloyed austenitic stainless steel and softer ferrous metal in a sintered compact, said microzones of austenitic stainless steel containing carbides and carbonitrides, and said insert made by a process comprising the steps of: forming a green compact essentially in the shape of said insert from a blend containing prealloyed austenitic stainless steel powder atomizate, a softer ferrous metal component and powdered carbon; and sintering said compact.
Claim 13
Dependent Claim
15 words
The compact of claim 9 wherein said softer ferrous metal component comprises martensitic stainless steel.
Claim 14
Dependent Claim
20 words
The compact of claim 9 wherein the weight proportion of austentic stainless steel is between about 25 and about 50%.
Claim 15
Dependent Claim
18 words
The compact of claim 9 which contains about 0-5% copper, up to 2.0% molybdenum, and about 0.05-5% manganese.
Claim 16
Dependent Claim
9 words
The compact of claim 9 which has been age-hardened.
Claim 17
Dependent Claim
72 words
A sintered metal compact comprising interspersed microzones of prealloyed austenitic stainless steel and softer ferrous metal, said microzones of austenitic stainless steel containing carbonides and carbonitrides, and said compact made by a process comprising the steps of: forming a green compact essentially in the shape of said sintered compact from a blend containing prealloyed austenitic stainless steel powder atomizate, a softer ferrous metal component and powdered carbon; and sintering said green compact.
Claim 18
Dependent Claim
72 words
A sintered metal compact comprising interspersed microzones of prealloyed austenitic stainless steel and softer ferrous metal, said microzones of austenitic stainless steel containing carbonides and carbonitrides, and said compact made by a process comprising the steps of: forming a green compact essentially in the shape of said sintered compact from a blend containing prealloyed austenitic stainless steel powder atomizate, a softer ferrous metal component and powdered carbon; and sintering said green compact.
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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) | 1991-02-08 | 1991-08-10 | 1992-02-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-02-08 | 1995-08-10 | 1996-02-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-02-08 | 1999-08-10 | 2000-02-09 | $7700.00 | Window Closed / Lapsed |