US4459363A
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US
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Synthesis of refractory materials
Assignee: United States, ENERGY THE, Secretary of, Department of
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Filing: 1983-08-16
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Granted: 1984-07-10
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Expires: 2003-08-16
Abstract
Abstract Refractory metal nitrides are synthesized during a self-propagating combustion process utilizing a solid source of nitrogren. For this purpose, a metal azide is employed, preferably NaN3. The azide is combusted with Mg or Ca, and a metal oxide is selected from Groups III-A, IV-A, III-B, IV-B, or a rare earth metal oxide. The mixture of azide, Ca or Mg and metal oxide is heated to the mixture's ignition temperature. At that temperature the mixture is ignited and undergoes self-sustaining combustion until the starter materials are exhausted, producing the metal nitride.
Inventors
- 👤 Joseph B. Holt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 11:24
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/515; C04B35/58; C04B35/58007; C01; C01B; C01B21/00; C01B21/06; C01B21/0602; C01B21/0615; C01B21/063; C01B21/064; C01B21/068; C01B21/076; C01B21/0761; C01B21/082; C01B21/0828; C04B35/622; C04B35/64; C04B35/65; C04B35/651; C01B21/0632; C01B21/0635; C01B21/072; C01P; C01P2004/00; C01P2004/80
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
85 words
A method of synthesizing refractory nitride compositions, comprising: (a) mixing a metal azide with Ca or Mg and at least a stoichiometric amount of a metal oxide selected from the group consisting of the rare earth metals, the metals of the III-A, IV-A, III-B, IV-B groups, or a mixture thereof; (b) heating the resulting mixture of step (a) until a mixture ignition temperature is attained; and (c) allowing the mixture from step (b) to combust in a self-propagating manner to form a refractory nitride composition.
Claim 2
Independent Claim
85 words
A method of synthesizing refractory nitride compositions, comprising: (a) mixing a metal azide with Ca or Mg and at least a stoichiometric amount of a metal oxide selected from the group consisting of the rare earth metals, the metals of the III-A, IV-A, III-B, IV-B groups, or a mixture thereof; (b) heating the resulting mixture of step (a) until a mixture ignition temperature is attained; and (c) allowing the mixture from step (b) to combust in a self-propagating manner to form a refractory nitride composition.
Claim 3
Dependent Claim
19 words
The method according to claim 1, wherein said ignition of step (b) is carried out in a nitrogen atmosphere.
Claim 4
Dependent Claim
27 words
The method according to claim 1, further comprising adding a solution of about 5 to 10 weight percent HCl to said nitride composition formed in step (c).
Claim 5
Dependent Claim
18 words
The method according to claim 1, wherein said metal azide is an alkaline earth or alkaline metal azide.
Claim 6
Dependent Claim
13 words
The method according to claim 1, wherein said azide is NaN 3 .
Claim 7
Dependent Claim
16 words
The method according to claim 1, wherein said azide and metal oxide are reacted with Mg.
Claim 8
Dependent Claim
22 words
The method according to claim 6, wherein said azide is NaN 3 and said metal oxide is B 2 O 3 .
Claim 9
Dependent Claim
20 words
The method according to claim 6, wherein said azide is NaN 3 and said metal oxide is SiO 2 .
Claim 10
Dependent Claim
20 words
The method according to claim 6, wherein said azide is NaN 3 and said metal oxide is TiO 2 .
Claim 11
Dependent Claim
20 words
The method according to claim 6, wherein said azide is NaN 3 and said metal oxide is ZrO 2 .
Claim 12
Dependent Claim
20 words
The method according to claim 6, wherein said azide is NaN 3 and said metal oxide is HfO 2 .
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) | 1987-07-10 | 1988-01-09 | 1988-07-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-07-10 | 1992-01-09 | 1992-07-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-07-10 | 1996-01-09 | 1996-07-10 | $7700.00 | Window Closed / Lapsed |