US3620690A
Expired / Lapsed
US
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Sintered austenitic-ferritic chromium-nickel steel alloy
Assignee: SSI Technologies LLC
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Filing: 1968-07-10
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Granted: 1971-11-16
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Expires: 1988-07-10
Abstract
Abstract Powdered austenitic chromium-nickel stainless steel is blended with a powdered metal ferrite stabilizer, such as molybdenum, and the resulting blend is sintered to produce a new steel, namely, an unwrought austenitic-ferritic chromium-nickel alloy having, as sintered, desirably high tensile and yield strengths and other desirable properties.
Inventors
- 👤 Theodore R Bergstrom
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 18:54
CPC Classifications
C; C22; C22C; C22C33/00; C22C33/02; C22C33/0207; C22C33/0257; C22C33/0278; C22C33/0285; Y; Y10; Y10S; Y10S75/00; Y10S75/95
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
43 words
Alloy according to claim 1 wherein said austenite at 1,250* to 1,350* C. is present in the amount of 90 to 40 volume percent and said ferrite at 1,250* to 1,350* C. is present in the amount of 10 to 60 volume percent.
Claim 2
Dependent Claim
34 words
Alloy according to claim 1, wherein said stainless steel of said ferrite phase further comprises a metal selected from the group consisting of molybdenum, titanium, vanadium, tungsten, chromium, zirconium, silicon, tantalum, and mixtures thereof.
Claim 3
Dependent Claim
17 words
Alloy according to claim 3, wherein said metal is 3 to 11 weight percent of said alloy.
Claim 4
Dependent Claim
22 words
Alloy according to claim 3, wherein said metal is molybdenum and it amounts to 5 to 7 weight percent of said alloy.
Claim 5
Dependent Claim
27 words
Alloy according to claim 1 having ''''as sintered'''' an ultimate tensile strength of 55,000 to 110,000 p.s.i., 0.2 percent offset yield strength of 25,000 to 80,000 p.s.i.
Claim 6
Dependent Claim
33 words
A permeable shaped article made of the alloy of claim 1, said article having ''''as sintered'''' tensile strength and absolute micronic rating values whose product is in the range of 200,000 to 500,000.
Claim 7
Dependent Claim
25 words
A relatively dense article made of the alloy of claim 6 and having an apparent density of 85 to 99 percent of the theoretical density.
Claim 8
Dependent Claim
34 words
Alloy according to claim 1 comprising 16.0 to 26.0 weight percent chromium, 6.0 to 22.0 weight percent nickel, and up to 0.03 to 0.25 weight percent carboN, based on the weight of said alloy.
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) | 1974-11-15 | 1975-05-17 | 1975-11-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-15 | 1979-05-17 | 1979-11-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-15 | 1983-05-17 | 1983-11-16 | $7700.00 | Window Closed / Lapsed |