US4851205A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Alpha-sialon powder and process for its production
Assignee: National Institute for Materials Science
•
Filing: 1986-10-21
•
Granted: 1989-07-25
•
Expires: 2006-10-21
Abstract
Abstract An alpha -SIALON powder composed essentially of alpha -SIALON having the formula Mx(Si,Al)12(O,N)16 wherein M is at least one element selected from the group consisting of Li, Mg, Ca, Mn, Y and lanthanide metals and O<x</=2.
Inventors
- 👤 Mamoru Mitomo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 02:21
CPC Classifications
C; C01; C01B; C01B21/00; C01B21/082; C01B21/0821; C01B21/0826; C04; C04B; C04B35/00; C04B35/515; C04B35/58; C04B35/597; C01P; C01P2004/00; C01P2004/60; C01P2004/61; C01P2004/62
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
170 words
An α-SIALON powder consisting essentially of α-SIALON having the formula M x (Si,Al) 12 (O,N) 16 , wherein M is at least one element selected from the group consisting of Li, Mg, Ca, Mn, Y and lanthanide metals, and 0<x≦2; wherein said α-SIALON powder is produced by a process comprising heating a mixture comprising silicon oxide or a silicon compound capable of forming silicon oxide when heated, aluminum oxide or an aluminum compound capable of forming aluminum oxide when heated, carbon, and an oxide of M or a compound of M capable of forming the oxide of M, in a nitrogen atmosphere at a temperature of from 1400° to 1700° C.; and wherein in said mixture, the atomic ratio of Al/Si is from about 0.025 to 0.5, the atomic ratio of M/Al is from about 0.12 to 0.77, and wherein said carbon is in an amount of from 1 to 5 times the sum of 2 times the number of Si atoms and 1.5 times the number of Al atoms.
Claim 2
Dependent Claim
170 words
An α-SIALON powder consisting essentially of α-SIALON having the formula M x (Si,Al) 12 (O,N) 16 , wherein M is at least one element selected from the group consisting of Li, Mg, Ca, Mn, Y and lanthanide metals, and 0<x≦2; wherein said α-SIALON powder is produced by a process comprising heating a mixture comprising silicon oxide or a silicon compound capable of forming silicon oxide when heated, aluminum oxide or an aluminum compound capable of forming aluminum oxide when heated, carbon, and an oxide of M or a compound of M capable of forming the oxide of M, in a nitrogen atmosphere at a temperature of from 1400° to 1700° C.; and wherein in said mixture, the atomic ratio of Al/Si is from about 0.025 to 0.5, the atomic ratio of M/Al is from about 0.12 to 0.77, and wherein said carbon is in an amount of from 1 to 5 times the sum of 2 times the number of Si atoms and 1.5 times the number of Al atoms.
Claim 3
Dependent Claim
32 words
The α-SIALON powder according to claim 1, wherein said silicon compound capable of forming silicon oxide when heated is selected from the group consisting of methyl silicate, ethyl silicate and sodium silicate.
Claim 4
Dependent Claim
37 words
The α-SIALON powder according to claim 1, wherein said aluminum compound capable of forming aluminum oxide when heated is selected from the group consisting of aluminum ethoxide, alumium propoxide, aluminum nitrate, aluminum sulfate, aluminum chloride and alum.
Claim 5
Dependent Claim
31 words
The α-SIALON powder according to claim 1, wherein said M metal compound is selected from the group consisting of a M metal sulfate, chloride, nitrate, lower alkoxide, carbonate, hydroxide and oxalate.
Claim 6
Dependent Claim
44 words
The α-SIALON powder according to claim 1, wherein said oxide of metal M or compound of metal M capable of forming the oxide of metal M is selected from the group consisting of yttrium oxide,magnesium oxide, erbium oxide, neodymium nitrate and dysprosium chloride hexahydrate.
Claim 7
Dependent Claim
55 words
The α-SIALON powder according to claim 1, wherein in said mixture, the atomic ratio of a monovalent metal M to Al is about 0.57 to 0.77, the atomic ratio of divalent metal M to Al is about 0.23 to 0.43, and the atomic ratio of trivalent metal M to Al is about 0.12 to 0.32.
Claim 8
Dependent Claim
21 words
The α-SIALON powder according to claim 1, wherein said powder has a particle size in the range of from 0.1-2 μm.
Claim 9
Dependent Claim
35 words
The α-SIALON powder according to claim 1, wherein said powder has a single phase of α-SIALON or an α-SIALON phase containing silicon nitride, β-SIALON, silicon carbide, aluminum nitride, silica, alumina or a M metal oxide.
Claim 10
Dependent Claim
20 words
The α-SIALON powder according to claim 1, wherein said powder contains at least 67% by wt. of said α-SIALON phase.
Claim 11
Dependent Claim
20 words
The α-SIALON powder according to claim 1, wherein said powder contains at least 92% by wt. of said α-SIALON phase.
Claim 12
Dependent Claim
15 words
The α-SIALON powder according to claim 1, wherein said lanthanide metal is neodymium or dysprosium.
Claim 13
Dependent Claim
165 words
A process for producing an α-SIALON powder consisting essentially of α-SIALON having the formula M x (Si,Al) 2 (O,N) 16 where M is at least one element selected from the group consisting of Li, Mg, Ca, Mn, Y and lanthanide metals and 0<x≦2, which comprises heating a mixture comprising silicon oxide or a silicon compound capable of forming silicon oxide when heated, aluminum oxide or an aluminum compound capable of forming aluminum oxide when heated, carbon, and an oxide of M or a compound of M capable of forming the oxide of M, in a nitrogen atmosphere at a temperature of from 1400° to 1700° C.; and wherein in said mixture, the atomic ratio of Al/Si is from about 0.025 to 0.5, the atomic ratio of M/Al is from about 0.12 to 0.77, and wherein said carbon is in an amount of from 1 to 5 times the sum of 2 times the number of Si atoms and 1.5 times the number of Al atoms.
Claim 14
Dependent Claim
165 words
A process for producing an α-SIALON powder consisting essentially of α-SIALON having the formula M x (Si,Al) 2 (O,N) 16 where M is at least one element selected from the group consisting of Li, Mg, Ca, Mn, Y and lanthanide metals and 0<x≦2, which comprises heating a mixture comprising silicon oxide or a silicon compound capable of forming silicon oxide when heated, aluminum oxide or an aluminum compound capable of forming aluminum oxide when heated, carbon, and an oxide of M or a compound of M capable of forming the oxide of M, in a nitrogen atmosphere at a temperature of from 1400° to 1700° C.; and wherein in said mixture, the atomic ratio of Al/Si is from about 0.025 to 0.5, the atomic ratio of M/Al is from about 0.12 to 0.77, and wherein said carbon is in an amount of from 1 to 5 times the sum of 2 times the number of Si atoms and 1.5 times the number of Al atoms.
Claim 15
Dependent Claim
44 words
The process of claim 12, wherein said mixture is obtained by dispersing carbon and an oxide of M or a compound of M capable of forming an oxide of M when heated, in a sol of silica and alumina and then separating the liquid.
Claim 16
Dependent Claim
54 words
The process of claim 12, wherein said mixture is obtained by dispersing carbon in a solution comprising a silicon compound capable of forming silica when heated, an aluminum compound capable of forming alumina when heated and a compound of M capable of forming an oxide of M when heated, and then reacting the solution.
Claim 17
Dependent Claim
17 words
The process of claim 13, wherein said heating is effected at a temperature of about 1450°-1650° C.
Claim 18
Dependent Claim
17 words
The process of claim 14, wherein said heating is effected at a temperature of about 1400°-1600° C.
Claim 19
Dependent Claim
42 words
The process of claim 12, wherein said oxide ofmetal M or compound of metal M capable of forming the oxide of metal M is selected from the group consisting of yttrium oxide, magnesium oxide, erbium oxide, neodymium nitrate and dysprosium chloride hexahydrate.
Claim 20
Dependent Claim
30 words
The process of claim 12, wherein said silicon compound capable of forming silicon oxide when heated is selected from the group consisting of methyl silicate, ethyl silicate and sodium silicate.
Claim 21
Dependent Claim
36 words
The process of claim 12, wherein said aluminum compound capable of forming an aluminum oxide when heated is selected from the group consisting of aluminum ethoxide, aluminum propoxide, aluminum nitrate, aluminum sulfate, aluminum chloride and alum.
Claim 22
Dependent Claim
29 words
The process of claim 12 wherein said compound of M is selected from the group consisting of a M metal sulfate, chloride, nitrate, lower alkoxide, carbonate, hydroxide and oxalate.
Claim 23
Dependent Claim
53 words
The process of claim 12, wherein in said mixture, the atomic ratio of a monovalent metal M to Al is about 0.57 to 0.77, the atomic ratio of divalent metal M to Al is about 0.23 to 0.43, and the atomic ratio of trivalent metal M to Al is about 0.12 to 0.32.
References Cited (Backward Citations)
US4360506A
Cited
JPS573769A
Cited
JPS57129873A
Cited
JPS5884914A
Cited
JPS5895608A
Cited
EP0087888A2
Cited
JPS5918106A
Cited
JPS59199580A
Cited
US4500644A
Cited
JPS60145902A
Cited
JPS60260410A
Cited
JPH0621864A
Cited
JPH06126567A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-07-24 | 1993-01-23 | 1993-07-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-07-24 | 1997-01-23 | 1997-07-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-07-24 | 2001-01-23 | 2001-07-25 | $7700.00 | Window Closed / Lapsed |