Patent US3856478A successfully refreshed from Google Patents.
US3856478A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fe-Mo-C-{8 Cr{9 {0 SINTERED ALLOYS FOR VALVE SEATS
Assignee: Mitsubishi Motors Corp
•
Filing: 1972-12-08
•
Granted: 1974-12-24
•
Expires: 1992-12-08
Abstract
Abstract Ferrous sintered alloys adapted for use as valve seats in internal combustion engines resistive to wear and intermetallic impact wear from the heated valve associated therewith, the alloys composed essentially of from 0.4-2.0 percent of carbon, 210 percent of molybdenum, optionally containing 0.5-5.2 percent chromium, the balance being iron plus minor impurities are disclosed. The valve seats made of the novel sintered alloys are particularly suited for engines burning lead-free gasoline or engines using LPG as the fuel.
Inventors
- 👤 T Iwata
- 👤 K Sakamoto
- 👤 M Nakano
- 👤 H Murayama
- 👤 T Nawata
- 👤 H Endo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 17:14
CPC Classifications
C; C22; C22C; C22C33/00; C22C33/02; C22C33/0257; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49229; Y10T29/49298; Y10T29/49306
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
117 words
A FERROUS SINTERED ALLOY VALVE SEAT HAVING IMPROVED IMPACT WEAR CHARACTERISTICS AND HAVING COATED OR HAVING UNIFORMLY DEPOSITED ON THE ENGAGING SURFACES THEREOF STABLE, DURABLE AND SELF-LUBRICATING PROTECTIVE OXIDE FILM SECURELY BONDED THERETO, SAID SURFACES AND VALVE SEAT CONTAINING SUITABLE VOIDS THEREIN ADAPTED TO RETAIN SAID PROTECTIVE OXIDE FILM; SAID ALLOY CONSISTING ESSENTIALLY OF 0.4-2.0 WEIGHT PERCENT CARBON, 2-10 WEIGHT PERCENT MOLYBDENUM IN THE FORM OF FERROMOLYBDENUM PARTICLES DISPERSED IN THE MICROSCOPIC METALLURGICAL STRUCTURE, BALANCE IRON; SAID ALLOY HAVING A HARDNESS VALUE (HVN) OF BETWEEN ABOUT 111 AND ABOUT 282; SAID VALVE SEAT PRESENT A DURABLE HOT IMPACT WEAR-RESISTANT SURFACE IN CONTACT WITH THE VALVE ASSOCIATED THEREWITH WITHOUT PROMOTING SUBSTANTIAL WEARING OF SAID VALVE UNDER HEATED CONDITIONS.
Claim 2
Dependent Claim
117 words
A FERROUS SINTERED ALLOY VALVE SEAT HAVING IMPROVED IMPACT WEAR CHARACTERISTICS AND HAVING COATED OR HAVING UNIFORMLY DEPOSITED ON THE ENGAGING SURFACES THEREOF STABLE, DURABLE AND SELF-LUBRICATING PROTECTIVE OXIDE FILM SECURELY BONDED THERETO, SAID SURFACES AND VALVE SEAT CONTAINING SUITABLE VOIDS THEREIN ADAPTED TO RETAIN SAID PROTECTIVE OXIDE FILM; SAID ALLOY CONSISTING ESSENTIALLY OF 0.4-2.0 WEIGHT PERCENT CARBON, 2-10 WEIGHT PERCENT MOLYBDENUM IN THE FORM OF FERROMOLYBDENUM PARTICLES DISPERSED IN THE MICROSCOPIC METALLURGICAL STRUCTURE, BALANCE IRON; SAID ALLOY HAVING A HARDNESS VALUE (HVN) OF BETWEEN ABOUT 111 AND ABOUT 282; SAID VALVE SEAT PRESENT A DURABLE HOT IMPACT WEAR-RESISTANT SURFACE IN CONTACT WITH THE VALVE ASSOCIATED THEREWITH WITHOUT PROMOTING SUBSTANTIAL WEARING OF SAID VALVE UNDER HEATED CONDITIONS.
Claim 3
Dependent Claim
17 words
The valve seat of claim 1 wherein said alloy additionally contains about 0.5 - 2.5 percent chromium.
Claim 4
Dependent Claim
73 words
A ferrous sintered alloy for valve seats of internal combustion engines, said valve seat exhibiting improved hot impact wear characteristics and having uniformly deposited on the engaging surfaces thereof a stable, desirable and self-lubricating protective oxide film securely bonded thereto, said surfaces and valve seat characterized by voids contained therein adapted to retain said protective oxide film, said alloy composed, in addition to iron, the following materials all expressed in percent by weight:
Claim 5
Dependent Claim
73 words
A ferrous sintered alloy for valve seats of internal combustion engines, said valve seat exhibiting improved hot impact wear characteristics and having uniformly deposited on the engaging surfaces thereof a stable, desirable and self-lubricating protective oxide film securely bonded thereto, said surfaces and valve seat characterized by voids contained therein adapted to retain said protective oxide film, said alloy composed, in addition to iron, the following materials all expressed in percent by weight:
Claim 6
Dependent Claim
45 words
A valve seat made of a sintered alloy consisting of 0.4 - 2.0 percent by weight of C, 2-10 percent by weight of Mo and the remainder essentially of Fe, and containing finely divided ferro-molybdenum particles dispersed in the microscopic metallurgical structure of said alloy.
Claim 7
Dependent Claim
45 words
A valve seat made of a sintered alloy consisting of 0.4 - 2.0 percent by weight of C, 2-10 percent by weight of Mo and the remainder essentially of Fe, and containing finely divided ferro-molybdenum particles dispersed in the microscopic metallurgical structure of said alloy.
Claim 8
Dependent Claim
49 words
A valve seat made of a sintered alloy consisting of 0.4-2.0 percent by weight of C, 2-10 percent by weight of Mo, 0.5-2.5 percent by weight of Cr and the remainder essentially of Fe, and containing finely divided ferro-molybdenum particles dispersed in the microscopic metallurgical structure of said alloy.
Claim 9
Dependent Claim
49 words
A valve seat made of a sintered alloy consisting of 0.4-2.0 percent by weight of C, 2-10 percent by weight of Mo, 0.5-2.5 percent by weight of Cr and the remainder essentially of Fe, and containing finely divided ferro-molybdenum particles dispersed in the microscopic metallurgical structure of said alloy.
Claim 10
Dependent Claim
21 words
The valve seat of claim 1 wherein said alloy has a hardness value (HVN) of between about 142 and about 263.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-12-23 | 1978-06-24 | 1978-12-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-23 | 1982-06-24 | 1982-12-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-23 | 1986-06-24 | 1986-12-24 | $7700.00 | Window Closed / Lapsed |