Patent US4141740A successfully refreshed from Google Patents.
US4141740A
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Solid solution and process for producing a solid solution
Assignee: University of Utah Research Foundation Inc
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Filing: 1978-02-23
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Granted: 1979-02-27
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Expires: 1998-02-23
Abstract
Abstract A solid solution and a process for producing a solid solution, the solid solution including at least the compounds: silicon carbide and aluminum oxycarbide, and also aluminum nitride. The new material including all three compounds is referred to by the acronym, SiCAlON, which is a coined term consisting of the chemical abbreviations for the elements present in the solid solution. The solid solution is obtained by heating an intimate mixture of reactants above about 1550 DEG C. The silicon carbide in the solid solution has the alpha or hexagonal structure and the aluminum nitride has the wurtzite or hexagonal structure. The solid solution is characterized by the substantial absence of iron or other impurities that tend to encourage the formation of silicon carbide as a separate phase having a beta or cubic structure.
Inventors
- 👤 Ivan B. Cutler
- 👤 Patrick D. Miller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 22:21
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/515; C04B35/56; C04B35/565; C04B35/01; C04B35/10; C04B35/111; C04B35/58; C04B35/581
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
35 words
A refractory product comprising a solid solution comprising aluminum nitride, silicon carbide, and aluminum oxycarbide wherein said solid solution comprises at least 1% by weight aluminum nitride and at least 1% by weight aluminum oxycarbide.
Claim 2
Dependent Claim
35 words
A refractory product comprising a solid solution comprising aluminum nitride, silicon carbide, and aluminum oxycarbide wherein said solid solution comprises at least 1% by weight aluminum nitride and at least 1% by weight aluminum oxycarbide.
Claim 3
Dependent Claim
40 words
The refractory product defined in claim 1 wherein the solid solution is particularly characterized by the substantial absence of impurities that tend to influence the formation of cubic structure silicon carbide wherein said impurities are less than 0.1% by weight.
Claim 4
Dependent Claim
99 words
A process for producing a refractory reaction product comprising silicon carbide, aluminum nitride, and aluminum oxycarbide in solid solution comprising: admixing a source of silicon, a source of aluminum, a source of nitrogen, and a source of carbon to form an intimate reaction mixture in such stoichiometric proportions that will yield a product containing at least 1% by weight aluminum nitride and at least 1% by weight aluminum oxycarbide in said solid solution; and heating said mixture at a temperature within the range on the order of about 1500° C. to 2000° C. until the solid solution is formed.
Claim 5
Dependent Claim
99 words
A process for producing a refractory reaction product comprising silicon carbide, aluminum nitride, and aluminum oxycarbide in solid solution comprising: admixing a source of silicon, a source of aluminum, a source of nitrogen, and a source of carbon to form an intimate reaction mixture in such stoichiometric proportions that will yield a product containing at least 1% by weight aluminum nitride and at least 1% by weight aluminum oxycarbide in said solid solution; and heating said mixture at a temperature within the range on the order of about 1500° C. to 2000° C. until the solid solution is formed.
Claim 6
Dependent Claim
48 words
The process defined in claim 3 wherein the admixing step further comprises obtaining a fume-type silica as the silicon source and precipitating an aluminum salt as the aluminum source in a solution containing the silica to obtain an intimate dispersion of the silicon source with the aluminum source.
Claim 7
Dependent Claim
60 words
The process defined in claim 3 wherein the admixing step further comprises mixing a clay with a carbon source, the clay having less than 0.1% by weight impurities therein and providing silica as the silicon source and alumina as the aluminum source, the heating step comprising heating the clay and carbon source under a nitrogen atmosphere as the nitrogen source.
Claim 8
Dependent Claim
70 words
A process for producing a solid solution comprising silicon carbide, aluminum nitride, and aluminum oxycarbide comprising: obtaining a clay having silica and alumina; removing impurities from the clay; mixing a carbon source with the clay to form a reactant mixture; heating the reactant mixture under a nitrogen atmosphere to a temperature within the range on the order of about 1500° C. to 2000° C. until said solid solution is formed.
Claim 9
Dependent Claim
70 words
A process for producing a solid solution comprising silicon carbide, aluminum nitride, and aluminum oxycarbide comprising: obtaining a clay having silica and alumina; removing impurities from the clay; mixing a carbon source with the clay to form a reactant mixture; heating the reactant mixture under a nitrogen atmosphere to a temperature within the range on the order of about 1500° C. to 2000° C. until said solid solution is formed.
Claim 10
Dependent Claim
14 words
A solid solution comprising silicon carbide and at least 1% by weight aluminum oxycarbide.
Claim 11
Dependent Claim
14 words
A solid solution comprising silicon carbide and at least 1% by weight aluminum oxycarbide.
Claim 12
Dependent Claim
20 words
The solid solution defined in claim 7 wherein the solid solution further comprises at least 1% by weight aluminum nitride.
Claim 13
Dependent Claim
25 words
The process defined in claim 3 wherein the solid solution is prepared from reactants comprising an intimate mixture of silica, carbon, and an aluminum source.
Claim 14
Dependent Claim
14 words
The process defined in claim 9 wherein the aluminum source is an aluminum salt.
Claim 15
Dependent Claim
12 words
The process defined in claim 9 wherein the aluminum source is alumina.
Claim 16
Dependent Claim
41 words
The process defined in claim 3 wherein the solid solution is prepared from reactants comprising an intimate mixture of clay from which impurities have been removed to less than 0.1% by weight and a carbon source, reacted under a nitrogen atmosphere.
Claim 17
Dependent Claim
31 words
The process defined in claim 3 wherein the solid solution is produced at a reaction temperature above about 1500° C. and below the decomposition temperatures of aluminum nitride and aluminum oxycarbide.
Claim 18
Dependent Claim
46 words
The solid solution defined in claim 3 wherein said solid solution is prepared from reactants comprising an intimate mixture of clay from which impurities have been removed to less than 0.1% by weight and a carbon source, said reactants having been reacted under an inert atmosphere.
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) | 1982-02-26 | 1982-08-28 | 1983-02-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-02-26 | 1986-08-28 | 1987-02-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-02-26 | 1990-08-28 | 1991-02-27 | $7700.00 | Window Closed / Lapsed |