US4082580A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Iron-nickel-molybdenum alloy having improved stability and high initial permeability
Assignee: Vacuumschmelze GmbH and Co KG
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Filing: 1974-10-31
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Granted: 1978-04-04
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Expires: 1994-10-31
Abstract
Abstract An alloy is described which contains between about 33 and 35% nickel, about 1 and 4% molybdenum and the balance iron with incidental impurities. The alloy is characterized by having a completely secondarily recrystallized structure, improved stability preventing substantial transformation to martensite at temperatures as low as -320° F, high resistance and high initial permeability.
Inventors
- 👤 Friedrich Pfeifer
- 👤 Gunter Klein
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 18:37
CPC Classifications
C; C21; C21D; C21D6/00; C21D6/001; C22; C22C; C22C38/00; C22C38/08
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
68 words
A heat treated magnetic alloy consisting essentially of from 33 to 35% nickel, from 1 to 4% molybdenum and the balance essentially iron the alloy prior to the last cold working exhibiting a fine grain structure and after the final heat treatment exhibiting a completely secondarily recrystallized structure, an initial permeability in excess of 20,000 Gauss/oersted and stability preventing substantial transformation to martensite at temperatures of -320° F.
Claim 2
Dependent Claim
68 words
A heat treated magnetic alloy consisting essentially of from 33 to 35% nickel, from 1 to 4% molybdenum and the balance essentially iron the alloy prior to the last cold working exhibiting a fine grain structure and after the final heat treatment exhibiting a completely secondarily recrystallized structure, an initial permeability in excess of 20,000 Gauss/oersted and stability preventing substantial transformation to martensite at temperatures of -320° F.
Claim 3
Dependent Claim
47 words
The alloy of claim 1 having a completely secondarily recrystallized structure after heat treating the alloy which has been cold worked to effect at least a 92% reduction in cross-sectional area, at a temperature within the range between 1050° C and 1250° C in a non-oxidizing atmosphere.
Claim 4
Dependent Claim
31 words
The alloy of claim 2 in which the alloy is given an intermediate anneal at a temperature within the range between the recrystallization temperature and 700° C prior to cold working.
References Cited (Backward Citations)
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US2930725A
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US3657026A
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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) | 1981-04-03 | 1981-10-03 | 1982-04-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-04-03 | 1985-10-03 | 1986-04-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-04-03 | 1989-10-03 | 1990-04-04 | $7700.00 | Window Closed / Lapsed |