US3814598A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Wear resistant powder metal magnetic pole piece made from oxide coated fe-al-si powders
Assignee: Chromalloy American Corp
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Filing: 1973-03-27
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Granted: 1974-06-04
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Expires: 1993-03-27
Abstract
Abstract A POWDER METALLURGY PRODUCED WEAR RESISTANT MAGNETIC POLE PIECE FOR USE AS A PICKUP HEAD WITH MAGNETIC PLAYBACK TAPES IS PROVIDED MADE FOR A MAGNETICALLY SOFT FERROUS ALLOY CONTAINING EFFECTIVE AMOUNTS OF SULICON AND ALUMINUM. A POWDER OF THE ALLOY IS OXIDIZED TO PROVIDE A THIN OXIDE ON THE PARTICLE THEREOF. THE POWDER IS THEN HOT PRESSED IN VACUUM AT AN ELEVATED TEMPERATURE INTOS DENSE SINERED BODY. THE PRESENCE OF OXIDE OF OXIDE IN THE GRAIN BOUNDRIES CONFERS WEAR RESISTANT PROPERTIES TO THE ALLOY AN OXYGEN CONTENT OF ABOUT 3400 TO 4400 P.P.M. IS PREFERRED.
Inventors
- 👤 J Gabriel
- 👤 W Reilly
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:55
CPC Classifications
C; C22; C22C; C22C33/00; C22C33/02; C22C33/0257; C22C33/0278; B; B22; B22F; B22F3/00; B22F3/12; B22F3/14; Y; Y10; Y10S; Y10S428/00; Y10S428/922; Y10S428/9265; Y10S428/928
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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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) | 1977-06-03 | 1977-12-03 | 1978-06-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-03 | 1981-12-03 | 1982-06-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-03 | 1985-12-03 | 1986-06-04 | $7700.00 | Window Closed / Lapsed |