Patent US4847220A successfully refreshed from Google Patents.
US4847220A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making ceramic composites
Assignee: Lanxide Technology Co LP
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Filing: 1987-07-06
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Granted: 1989-07-11
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Expires: 2007-07-06
Abstract
Abstract The invention relates to a method for producing ceramic composites obtained by oxidation of an aluminum parent metal to form a polycrystalline ceramic material by providing a filler having a coating of a silicon source on at least a portion of said filler different in composition from the primary composition of said filler, said silicon source possessing intrinsic doping properties. A body of molten parent metal, adjacent a mass of the filler material, reacts with an oxidant to form an oxidation reaction product which infiltrates the adjacent mass of filler thereby forming the ceramic composite.
Inventors
- 👤 H. Daniel Lesher
- 👤 Christopher R. Kennedy
- 👤 Danny R. White
- 👤 Andrew W. Urquhart
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 12:20
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/01; C04B35/14; C04B35/622; C04B35/64; C04B35/65; C04B35/652; C04B35/71; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2913; Y10T428/2933; Y10T428/2938; Y10T428/2962
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
261 words
A method for producing a self-supporting ceramic composite comprising a ceramic matrix obtained by oxidation of an aluminum parent metal to form a polycrystalline material comprising oxidation reaction product of the parent metal with at least one oxidant including a vapor-phase oxidant and a filler infiltrated by said matrix, said method comprising: (A) orienting said aluminum parent metal and a filler material relative to each other so that formation of the oxidation reaction product will occur in a direction towards and into said filler, said filler material bearing a coating of a silicon source on at least a portion of said filler different in composition from a primary composition of said filler, said silicon source possessing intrinsic doping properties; (B) heating said aluminum parent metal to a temperature above its melting point but below the melting point of the oxidation reaction product to form a body of molten aluminum parent metal; (C) reacting the molten aluminum parent metal with said oxidant at said temperature to form the oxidation reaction product; (D) maintaining at said temperature at least a portion of said oxidation reaction product in contact with and between said body of molten metal and said oxidant, to progressively draw molten metal through the oxidation reaction product towards the oxidant and into the filler material so that fresh oxidation reaction product continues to form within said filler at an interface between the oxidant and previously formed oxidation reaction product; and (E) continuing said reaction for a time sufficient to infiltrate at least a portion of said filler with said polycrystalline material.
Claim 2
Independent Claim
261 words
A method for producing a self-supporting ceramic composite comprising a ceramic matrix obtained by oxidation of an aluminum parent metal to form a polycrystalline material comprising oxidation reaction product of the parent metal with at least one oxidant including a vapor-phase oxidant and a filler infiltrated by said matrix, said method comprising: (A) orienting said aluminum parent metal and a filler material relative to each other so that formation of the oxidation reaction product will occur in a direction towards and into said filler, said filler material bearing a coating of a silicon source on at least a portion of said filler different in composition from a primary composition of said filler, said silicon source possessing intrinsic doping properties; (B) heating said aluminum parent metal to a temperature above its melting point but below the melting point of the oxidation reaction product to form a body of molten aluminum parent metal; (C) reacting the molten aluminum parent metal with said oxidant at said temperature to form the oxidation reaction product; (D) maintaining at said temperature at least a portion of said oxidation reaction product in contact with and between said body of molten metal and said oxidant, to progressively draw molten metal through the oxidation reaction product towards the oxidant and into the filler material so that fresh oxidation reaction product continues to form within said filler at an interface between the oxidant and previously formed oxidation reaction product; and (E) continuing said reaction for a time sufficient to infiltrate at least a portion of said filler with said polycrystalline material.
Claim 3
Dependent Claim
23 words
The method of claim 1, wherein said silicon source comprises a silicic compound reducible by said molten parent metal under the process conditions.
Claim 4
Dependent Claim
22 words
The method of claim 1, wherein said coating of said silicon source is produced by oxidation or dissociation of a silicic precursor.
Claim 5
Dependent Claim
27 words
The method of claim 3, wherein said oxidation or dissociation to produce said coating of said silicon source is conducted prior to said orienting step in (A).
Claim 6
Independent Claim
34 words
The method of claims 3, or 4, wherein said oxidation to form said coating is conducted by heating said silicon source in the presence of an oxygen-containing atmosphere to form a coating of silica.
Claim 7
Independent Claim
32 words
The method of any of claims 1, 2, 3, or 4, wherein said filler comprises a material selected from the group consisting of silicon carbide, silicon nitride, alumina, zirconia, and boron nitride.
Claim 8
Independent Claim
30 words
The method of any of claims 1, 2, 3, or 4, wherein said heating step in (B) is at a temperature of from about 700° C. to about 1450° C.
Claim 9
Independent Claim
31 words
The method of any of claims 1, 2, 3, or 4, additionally comprising using at least one dopant material, in addition to said silicon source, in conjunction with said parent metal.
Claim 10
Independent Claim
24 words
The method of any of claims 1, 2, 3, or 4, additionally comprising shaping said filler material into at least one permeable, self-supporting preform.
Claim 11
Dependent Claim
29 words
The method of claim 9, additionally comprising overlaying at least a portion of said preform with a barrier means for inhibiting the formation of said oxidation reaction product therebeyond.
Claim 12
Independent Claim
75 words
The method of any of claims 1, 2, 3, or 4, further comprising incorporating at least one additional oxidant selected from the group consisting of a solid oxidant and a liquid oxidant into at least a portion of said filler material, and reacting said molten metal with said at least one additional oxidant, so that said polycrystalline material further comprises the oxidation reaction product of said parent metal with said at least one additional oxidant.
Claim 13
Dependent Claim
28 words
The method of claim 1 or claim 2, wherein said silicon source comprises at least one material selected from the group consisting of silica, a silicate, and silicon.
Claim 14
Dependent Claim
33 words
The method of claim 4, wherein said oxidation to produce said coating utilizes an oxidant comprising an oxidant selected from the group consisting of a nitrogen-containing gas, an oxygen-containing gas and mixtures thereof.
Claim 15
Independent Claim
274 words
A method for producing a self-supporting ceramic composite comprising a ceramic matrix obtained by oxidation of an aluminum parent metal to form a polycrystalline material comprising oxidation reaction product of the parent metal with at least one oxidant including a vapor-phase oxidant and a filler infiltrated by said matrix, said method comprising: (a) orienting said aluminum parent metal and a filler material relative to each other so that formation of the oxidation reaction product will occur in a direction towards and into said filler; (b) heating said aluminum parent metal and said filler to a temperature above the melting point of the parent metal but below the melting point of the oxidation reaction product to form a body of molten aluminum parent metal, said filler oxidizing or dissociating at said temperature to produce a coating of a silicon source on at least a portion of said filler different in composition from a primary composition of said filler, said silicon source possessing intrinsic doping properties; (c) reacting the molten aluminum parent metal with said oxidant at said temperature to form the oxidation reaction product; (d) maintaining at said temperature at least a portion of said oxidation reaction product in contact with and between said body of molten metal and said oxidant, to progressively draw molten metal through the oxidation reaction product towards the oxidant and into the filler material so that fresh oxidation reaction product continues to form within said filler at an interface between the oxidant and previously formed oxidation reaction product; and (e) continuing said reaction for a time sufficient to infiltrate at least a portion of said filler with said polycrystalline material.
Claim 16
Independent Claim
274 words
A method for producing a self-supporting ceramic composite comprising a ceramic matrix obtained by oxidation of an aluminum parent metal to form a polycrystalline material comprising oxidation reaction product of the parent metal with at least one oxidant including a vapor-phase oxidant and a filler infiltrated by said matrix, said method comprising: (a) orienting said aluminum parent metal and a filler material relative to each other so that formation of the oxidation reaction product will occur in a direction towards and into said filler; (b) heating said aluminum parent metal and said filler to a temperature above the melting point of the parent metal but below the melting point of the oxidation reaction product to form a body of molten aluminum parent metal, said filler oxidizing or dissociating at said temperature to produce a coating of a silicon source on at least a portion of said filler different in composition from a primary composition of said filler, said silicon source possessing intrinsic doping properties; (c) reacting the molten aluminum parent metal with said oxidant at said temperature to form the oxidation reaction product; (d) maintaining at said temperature at least a portion of said oxidation reaction product in contact with and between said body of molten metal and said oxidant, to progressively draw molten metal through the oxidation reaction product towards the oxidant and into the filler material so that fresh oxidation reaction product continues to form within said filler at an interface between the oxidant and previously formed oxidation reaction product; and (e) continuing said reaction for a time sufficient to infiltrate at least a portion of said filler with said polycrystalline material.
Claim 17
Dependent Claim
32 words
The method of claim 14, wherein said oxidation to form said coating is conducted by heating said silicon source in the presence of an oxygen-containing atmosphere to form a coating of silica.
Claim 18
Dependent Claim
24 words
The method of claim 14, wherein said heating step in (b) is at a temperature of from about, 700° C. to about 1450° C.
Claim 19
Dependent Claim
66 words
The method of claim 14, wherein said heating step in (b) is conducted in the presence of an oxygen-containing atmosphere at a temperature of from about 1000° C. to about 1450° C. to produce said coating of said silicon source, and after said coating has formed in situ on a substantial portion of said filler, altering the temperature to continue formation of said oxidation reaction product.
Claim 20
Dependent Claim
25 words
The method of claim 14, further comprising using at least one dopant material, in addition to said silicon source, in conjunction with said parent metal.
Claim 21
Dependent Claim
18 words
The method of claim 14, further comprising shaping said filler material into at least one permeable, self-supporting preform.
Claim 22
Dependent Claim
29 words
The method of claim 14, further comprising overlaying at least a portion of said preform with a barrier means for inhibiting the formation of said oxidation reaction product therebeyond.
Claim 23
Dependent Claim
69 words
The method of claim 14, further comprising incorporating at least one additional oxidant selected from the group consisting of a solid oxidant and a liquid oxidant into at least a portion of said filler material, and reacting said molten metal with said at least one additional oxidant, so that said polycrystalline material further comprises the oxidation reaction product of said parent metal with said at least one additional oxidant.
Claim 24
Dependent Claim
37 words
The method of claim 1 or claim 14, wherein said vapor-phase oxidant used to form said oxidation reaction product comprises an oxidant selected from the group consisting of a nitrogen-containing gas, an oxygen-containing gas and mixtures thereof.
Claim 25
Dependent Claim
33 words
The method of claim 22, wherein said vapor-phase oxidant comprises an oxidant selected from the group consisting of air, a H 2 /H 2 O mixture, a CO/CO 2 mixture, and mixtures thereof.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-07-10 | 1993-01-09 | 1993-07-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-07-10 | 1997-01-09 | 1997-07-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-07-10 | 2001-01-09 | 2001-07-11 | $7700.00 | Window Closed / Lapsed |