US4374701A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Chemically polished ceramic body
Assignee: General Electric Co
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Filing: 1981-08-03
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Granted: 1983-02-22
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Expires: 2001-08-03
Abstract
Abstract An alkali metal beta- and/or beta"-alumina polycrystalline body is chemically polished by contacting it at a polishing temperature with phosphoric acid of polishing concentration.
Inventors
- 👤 Raj N. Singh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 14:47
CPC Classifications
H; H01; H01M; H01M10/00; H01M10/36; H01M10/39; H01M10/3909; H01M10/3918; C; C04; C04B; C04B41/00; C04B41/53; C04B41/5338; C04B41/5353; C09; C09K; C09K13/00; C09K13/04; Y; Y02; Y02E; Y02E60/00; Y02E60/10
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
125 words
A process for producing a polished ceramic body which comprises providing a polycrystalline ceramic body, said ceramic body ranging in composition from an alkali metal beta-alumina phase to an alkali metal beta"-alumina phase including all combinations of said alkali metal beta-alumina phase and said alkali metal beta"-alumina phase, said alkali metal being selected from the group consisting of sodium, potassium. lithium, mixtures thereof, and alloys thereof, and polishing said ceramic body by contacting it with phosphoric acid at a temperature ranging from about 250° C. to about 350° C. to produce a ceramic body with a polished surface, said phosphoric acid having a concentration of P 2 O 5 which polishes said ceramic body, said polishing having no significant deleterious effect on said ceramic body.
Claim 2
Dependent Claim
125 words
A process for producing a polished ceramic body which comprises providing a polycrystalline ceramic body, said ceramic body ranging in composition from an alkali metal beta-alumina phase to an alkali metal beta"-alumina phase including all combinations of said alkali metal beta-alumina phase and said alkali metal beta"-alumina phase, said alkali metal being selected from the group consisting of sodium, potassium. lithium, mixtures thereof, and alloys thereof, and polishing said ceramic body by contacting it with phosphoric acid at a temperature ranging from about 250° C. to about 350° C. to produce a ceramic body with a polished surface, said phosphoric acid having a concentration of P 2 O 5 which polishes said ceramic body, said polishing having no significant deleterious effect on said ceramic body.
Claim 3
Dependent Claim
12 words
The process according to claim 1 wherein said alkali metal is sodium.
Claim 4
Dependent Claim
28 words
The process according to claim 1 wherein said ceramic body contains alkali metal beta"-alumina phase and a stabilizer for said alkali metal beta"-alumina phase in a stabilizing amount.
Claim 5
Dependent Claim
25 words
The process according to claim 3 wherein said stabilizer is selected from the group consisting of Li 2 O, MgO, NiO, CoO and mixtures thereof.
Claim 6
Dependent Claim
165 words
A process for producing a cationically-conductive ceramic body having a polished surface and a specific resistivity at its polished surface portion which is at least not significantly different from its specific intrinsic resistivity which comprises providing a cationically-conductive ceramic body having a specific resistivity at its surface portion significantly higher than its specific intrinsic resistivity, said ceramic body ranging in composition from an alkali metal beta-alumina phase to an alkali metal beta"-alumina phase including all combinations of said alkali metal beta-alumina phase and said alkali metal beta"-alumina phase, said alkali metal being selected from the group consisting of sodium, potassium, lithium, mixtures thereof and alloys thereof, and polishing said ceramic body by contacting it with phosphoric acid at a temperature ranging from about 250° C. to about 350° C. to produce said cationically-conductive body with a polished surface, said phosphoric acid having a concentration of P 2 O 5 which polishes said ceramic body, said polishing having no significant deleterious effect on said ceramic body.
Claim 7
Dependent Claim
165 words
A process for producing a cationically-conductive ceramic body having a polished surface and a specific resistivity at its polished surface portion which is at least not significantly different from its specific intrinsic resistivity which comprises providing a cationically-conductive ceramic body having a specific resistivity at its surface portion significantly higher than its specific intrinsic resistivity, said ceramic body ranging in composition from an alkali metal beta-alumina phase to an alkali metal beta"-alumina phase including all combinations of said alkali metal beta-alumina phase and said alkali metal beta"-alumina phase, said alkali metal being selected from the group consisting of sodium, potassium, lithium, mixtures thereof and alloys thereof, and polishing said ceramic body by contacting it with phosphoric acid at a temperature ranging from about 250° C. to about 350° C. to produce said cationically-conductive body with a polished surface, said phosphoric acid having a concentration of P 2 O 5 which polishes said ceramic body, said polishing having no significant deleterious effect on said ceramic body.
Claim 8
Dependent Claim
12 words
The process according to claim 5 wherein said alkali metal is sodium.
Claim 9
Dependent Claim
28 words
The process according to claim 5 wherein said ceramic body contains alkali metal beta"-alumina phase and a stabilizer for said alkali metal beta"-alumina phase in a stabilizing amount.
Claim 10
Dependent Claim
25 words
The process according to claim 7 wherein said stabilizer is selected from the group consisting of Li 2 O, MgO, NiO, CoO and mixtures thereof.
Claim 11
Dependent Claim
141 words
A process for producing a cationically-conductive ceramic electrolyte of symmetric polarization which comprises providing a cationically-conductive ceramic electrolyte of asymmetric polarization, said electrolyte ranging in composition from an alkali metal beta"-alumina phase to a mixture of alkali metal beta"-alumina phase and up to about 50% by volume of alkali metal beta-alumina phase based on the total volume of the electrolyte, said alkali metal being selected from the group consisting of sodium, potassium, lithium, mixtures thereof and alloys thereof, and polishing said ceramic electrolyte by contacting it with phosphoric acid at a temperature ranging from about 250° C. to about 350° C. to produce said cationically-conductive ceramic electrolyte of symmetric polarization having a polished surface, said phosphoric acid having a concentration of P 2 O 5 which polishes said ceramic body, said polishing having no significant deleterious effect on said ceramic electrolyte.
Claim 12
Dependent Claim
141 words
A process for producing a cationically-conductive ceramic electrolyte of symmetric polarization which comprises providing a cationically-conductive ceramic electrolyte of asymmetric polarization, said electrolyte ranging in composition from an alkali metal beta"-alumina phase to a mixture of alkali metal beta"-alumina phase and up to about 50% by volume of alkali metal beta-alumina phase based on the total volume of the electrolyte, said alkali metal being selected from the group consisting of sodium, potassium, lithium, mixtures thereof and alloys thereof, and polishing said ceramic electrolyte by contacting it with phosphoric acid at a temperature ranging from about 250° C. to about 350° C. to produce said cationically-conductive ceramic electrolyte of symmetric polarization having a polished surface, said phosphoric acid having a concentration of P 2 O 5 which polishes said ceramic body, said polishing having no significant deleterious effect on said ceramic electrolyte.
Claim 13
Dependent Claim
12 words
The process according to claim 9 wherein said alkali metal is sodium.
Claim 14
Dependent Claim
23 words
The process according to claim 9 wherein said ceramic body contains a stabilizer for said alkali metal beta"-alumina phase in a stabilizing amount.
Claim 15
Dependent Claim
25 words
The process according to claim 11 wherein said stabilizer is selected from the group consisting of Li 2 O, MgO, NiO, CoO and mixtures thereof.
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) | 1986-02-21 | 1986-08-23 | 1987-02-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-02-21 | 1990-08-23 | 1991-02-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-02-21 | 1994-08-23 | 1995-02-22 | $7700.00 | Window Closed / Lapsed |