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US3607753A
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Method of making lithium ferrite powders
Assignee: United States Department of the Army
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Filing: 1967-11-16
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Granted: 1971-09-21
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Expires: 1987-11-16
Abstract
Abstract Ceramic powders of uniform and fine particle size are made by freeze drying a liquid solution of ceramic forming metallic salts, subliming the solvent, and applying heat to decompose the remaining solute to a ceramic powder.
Inventors
- 👤 Lydia A Suchoff
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 16:27
CPC Classifications
B; B82; B82Y; B82Y30/00; B01; B01J; B01J2/00; C; C01; C01B; C01B13/00; C01B13/14; C01B13/18; C01G; C01G49/00; C01G49/0018; C01G49/0027; C01G49/009; C04; C04B; C04B35/00; C04B35/01; C04B35/26; C04B35/2608; C04B35/2616; C04B35/2691; H; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/032; H01F1/10; H01F1/11; C01P; C01P2004/00; C01P2004/60; C01P2004/64
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
60 words
A method of making lithium ferrite ceramic powder of uniform and fine particle size comprising preparing an aqueous solution of lithium oxalate and ferric oxalate, adding the solution dropwise to liquid nitrogen, placing the frozen solution in a vacuum chamber and evacuating to remove all water, and decomposing the oxalates at least about 200* C. to obtain the lithium ferrite.
Claim 2
Independent Claim
60 words
A method of making lithium ferrite ceramic powder of uniform and fine particle size consisting of preparing an aqueous solution of lithium oxalate and ferric oxalate, adding the solution dropwise to liquid nitrogen, placing the frozen solution in a vacuum chamber and evacuating to remove all water, and decomposing the oxalates at about 300* C. to obtain the lithium ferrite.
Claim 3
Independent Claim
79 words
A method of making lithium zinc ferrite ceramic powder of uniform and fine particle size comprising preparing an aqueous solution of the oxalates of lithium, zinc and iron in the ratio of 4 parts lithium to 2 parts zinc to 22.8 parts iron, adding the solution dropwise to liquid nitrogen, placing the solution in a vacuum chamber and evacuating to remove all water, and decomposing the oxalates at about 200* to 300* C. to obtain the lithium zinc ferrite.
Claim 4
Independent Claim
80 words
A method of making lithium zinc ferrite ceramic powder of uniform and fine particle size comprising preparing an aqueous solution of the oxalates of lithium, zinc and iron in the ratio of 4 parts lithium to 2 parts zinc to 22.8 parts iron, adding the solution dropwise to liquid nitrogen, placing the frozen solution in a vacuum chamber and evacuating to remove all water, and decomposing the oxalates at at least about 200* C. to obtain the lithium zinc ferrite.
Claim 5
Independent Claim
79 words
A method of making lithium zinc ferrite ceramic powder of uniform and fine particle size consisting of preparing an aqueous solution of the oxalates of lithium, zinc and iron in the ratio of 4 parts lithium to 2 parts zinc to 22.8 parts iron, adding the solution dropwise to liquid nitrogen, placing the frozen solution in a vacuum chamber and evacuating to remove all water, and decomposing the oxalates at about 300* C. to obtain the lithium zinc ferrite.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-09-20 | 1975-03-22 | 1975-09-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-09-20 | 1979-03-22 | 1979-09-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-09-20 | 1983-03-22 | 1983-09-21 | $7700.00 | Window Closed / Lapsed |