US4657879A
Expired / Lapsed
US
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Silicate superionic conductors and method of making same
Assignee: MINISTER OF ENERGY MINES AND RESOURCES
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Filing: 1984-09-25
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Granted: 1987-04-14
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Expires: 2004-09-25
Abstract
Abstract The spray-drying of a feed liquid mixture containing dissolved feed elements is used to produce precursor powders of Na+-super conducting sodium gadolinium silicate (Na5GdSi4O12), (NGS), and sodium yttrium silicate (Na5YSi4O12), NYS. Using these powders, very dense (>97% theoretical) solids are obtained on sintering. The resistivities of the NGS and NYS polycrystalline ceramics are 5 and 7 ( OMEGA cm) respectively at 300 DEG C. and are dependent on the f(NGS) or f(NYS) values. In the case of NYS, the resistivity/f(NYS) relationship takes the form <IMAGE> indicative of resistive and conductive phases mixed more in parallel than in series.
Inventors
- 👤 Patrick S. Nicholson
- 👤 Kimihiro Yamashita
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 19:28
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/01; C04B35/16; C01; C01B; C01B33/00; C01B33/20; H; H01; H01M; H01M10/00; H01M10/36; H01M10/39; H01M10/3909; H01M10/3918; H01M6/00; H01M6/14; H01M6/18; H01M6/185; Y; Y02; Y02E; Y02E60/00; Y02E60/10; Y10; Y10S; Y10S505/00; Y10S505/80; Y10S505/801; Y10S505/809; Y10S505/815
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
117 words
A method of producing a fine polycrystalline powder of Na 5 RESi 4 O 12 , where RE=Gd or Y, comprising the steps of; (a) selecting, as a feed material, water soluble compounds of sodium, and of a rare earth, that is selected either as a water soluble compound of Gd or of Y; (b) dissolving in solution, the selected feed materials wherein rare earth atoms are in concentrations ranging from 0.1M and 0.3M; (c) spraying the dissolved solution of step (b) into a hot air stream whereupon the solution is dried into minute powder; (d) calcinating the resultant powders of step (c); and, (e) reducing the physical size of the powders to at least 200 mesh.
Claim 2
Independent Claim
117 words
A method of producing a fine polycrystalline powder of Na 5 RESi 4 O 12 , where RE=Gd or Y, comprising the steps of; (a) selecting, as a feed material, water soluble compounds of sodium, and of a rare earth, that is selected either as a water soluble compound of Gd or of Y; (b) dissolving in solution, the selected feed materials wherein rare earth atoms are in concentrations ranging from 0.1M and 0.3M; (c) spraying the dissolved solution of step (b) into a hot air stream whereupon the solution is dried into minute powder; (d) calcinating the resultant powders of step (c); and, (e) reducing the physical size of the powders to at least 200 mesh.
Claim 3
Independent Claim
141 words
A method of producing a ceramic as solid polycrystalline rare earth sodium silicate by; (a) selecting, as a feed material, water soluble compounds of sodium, and of a rare earth, that is selected either as a water soluble compound of Gd or of Y; (b) dissolving in solution, the selected feed materials wherein rare earth atoms are in concentrations ranging from 0.1M and 0.3M; (c) spraying the dissolved solution of step (b) into a hot air stream whereupon the solution is dried into minute powder; (d) calcinating the resultant powders of step (c); (e) reducing the physical size of the powders to at least 200 mesh; (f) compressing the powder of step (e) isostatically at between 30 to 60 kpsi; and, (g) sintering the pressed items of step (f) at between 1100° C. to 1180° C. for less than 30 minutes.
Claim 4
Independent Claim
141 words
A method of producing a ceramic as solid polycrystalline rare earth sodium silicate by; (a) selecting, as a feed material, water soluble compounds of sodium, and of a rare earth, that is selected either as a water soluble compound of Gd or of Y; (b) dissolving in solution, the selected feed materials wherein rare earth atoms are in concentrations ranging from 0.1M and 0.3M; (c) spraying the dissolved solution of step (b) into a hot air stream whereupon the solution is dried into minute powder; (d) calcinating the resultant powders of step (c); (e) reducing the physical size of the powders to at least 200 mesh; (f) compressing the powder of step (e) isostatically at between 30 to 60 kpsi; and, (g) sintering the pressed items of step (f) at between 1100° C. to 1180° C. for less than 30 minutes.
Claim 5
Dependent Claim
30 words
The method as claimed in claim 1 or 2, wherein the rare earths selected are in the form respectively as Gd(CH 3 COO) 3 and Y(NO 3 ) 3 .
Claim 6
Dependent Claim
34 words
The method as claimed in claim 1 or 2, wherein the rare earths selected are in the form respectively as Gd(CH 3 COO) 3 and Y(NO 3 ) 3 and each is 99.9% pure.
Claim 7
Dependent Claim
45 words
The method as claimed in claim 1, wherein step (a) the said Gd or Y atoms respectively reside as Gd(CH 3 COO) 3 and Y(NO 3 ) 3 and each is 99.9% pure and, wherein sodium compounds are selected from sodium carbonate and sodium silicate.
Claim 8
Dependent Claim
44 words
The method as claimed in claim 1 or 2, wherein the rare earths selected are in the form respectively as Gd(CH 3 COO) 3 and Y(NO 3 ) 3 and each is 99.9% pure and the sodium compounds are sodium carbonate and sodium silicate.
Claim 9
Dependent Claim
24 words
The method as claimed in claim 1 or 2, wherein step (c) maintains the spray-drying in the range of 75° C. to 220° C.
Claim 10
Dependent Claim
49 words
The method as claimed in claim 1 or 2, wherein the rare earths selected are in the form respectively as Gd(CH 3 COO) 3 and Y(NO 3 ) 3 and each is 99.9% pure wherein step (c) maintains the spray-drying in the range of 75° C. to 220° C.
Claim 11
Dependent Claim
60 words
The method as claimed in claim 1, wherein step (a) the said Gd or Y atoms respectively reside as Gd(CH 3 COO) 3 and Y(NO 3 ) 3 and each is 99.9% pure and, wherein sodium compounds are selected from sodium carbonate and sodium silicate wherein step (c) maintains the spray-drying in the range of 75° C. to 220° C.
Claim 12
Dependent Claim
59 words
The method as claimed in claim 1 or 2, wherein the rare earths selected are in the form respectively as Gd(CH 3 COO) 3 and Y(NO 3 ) 3 and each is 99.9% pure and the sodium compounds are sodium carbonate and sodium silicate wherein step (c) maintains the spray-drying in the range of 75° C. to 220° C.
Claim 13
Dependent Claim
30 words
The method as claimed in claim 2, wherein the rare earth selected is Gd (CH 3 COO) 3 and the sintering temperature of step (g) is at approximately 1100° C.
Claim 14
Dependent Claim
39 words
The method as claimed in claim 2, wherein the rare earth selected is Gd(CH 3 COO) 3 and the sintering temperature of step (g) is at approximately 1100° C., while the compression step (f) is at approximately 40 kpsi.
Claim 15
Dependent Claim
30 words
The method as claimed in claim 2, wherein the rare earth selected is Y(NO 3 ) 3 ; and the sintering temperature of step (g) is at approximately 1180° C.
Claim 16
Dependent Claim
40 words
The method as claimed in claim 2, wherein the rare earth selected is Y(NO 3 ) 3 ; and the sintering temperature of step (g) is at approximately 1180° C., while the compression step (e) is at approximately 40 kpsi.
Claim 17
Dependent Claim
25 words
The method as claimed in claim 11 or 12, wherein the step (c) maintains the spray-drying in the range of 75° C. to 220° C.
Claim 18
Dependent Claim
25 words
The method as claimed in claim 13 or 14, wherein the step (c) maintains the spray-drying in the range of 75° C. to 220° C.
References Cited (Backward Citations)
US4097345A
Cited
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