US4837230A
Expired / Lapsed
US
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Structural ceramic materials having refractory interface layers
Assignee: Rockwell Collins ElectroMechanical Systems Inc
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Filing: 1988-07-21
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Granted: 1989-06-06
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Expires: 2008-07-21
Abstract
Abstract Ceramic composite articles having high flexural and tensile strength are produced by introducing multiple layers of a ceramic matrix material onto a ceramic reinforcement fabric. Crack propagation in the resulting structure is inhibited by applying refractory interface layers intermediate successive ceramic matrix layers. Such ceramic composite articles are particularly useful for high temperature applications requiring a high degree of strength, such as rocket motor insulation and turbine blades, combustion chambers, and after burners for jet motors.
Inventors
- 👤 Shih-Huei Chen
- 👤 H. O. Davis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 16:30
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/71; C04B35/78; C04B35/80; C04B35/83; B; B32; B32B; B32B18/00; C04B35/01; C04B35/10; C04B35/111; C04B35/117; C04B35/16; C04B35/18; C04B35/185; C04B35/515; C04B35/56; C04B35/565; C04B35/571; C04B35/622; C04B35/626; C04B35/62605; C04B35/62625; C04B35/6263; C04B35/6269; C04B35/628; C04B35/62844; C04B35/62847; C04B35/62849; C04B35/62852; C04B35/62857; C04B35/62865; C04B35/62868; C04B35/62873; C04B35/62876; C04B35/62884; C04B35/62886; C04B35/62897; C04B35/63; C04B35/632; C04B35/6325; C04B2235/00; C04B2235/02; C04B2235/30; C04B2235/38; C04B2235/3817; C04B2235/3826; C04B2235/50; C04B2235/52; C04B2235/5208; C04B2235/5216; C04B2235/522; C04B2235/5224; C04B2235/5232; C04B2235/524; C04B2235/5244; C04B2235/5248; C04B2235/5276; C04B2235/60; C04B2235/602; C04B2235/6021; C04B2235/616; C04B2235/65; C04B2235/656; C04B2235/6562; C04B2235/6567; C04B2235/658; C04B2235/6581; C04B2235/66; C04B2235/661; C04B2235/70; C04B2235/74; C04B2235/77; C04B2235/96; C04B2237/00; C04B2237/30; C04B2237/32; C04B2237/34; C04B2237/341; C04B2237/343; C04B2237/36; C04B2237/363; C04B2237/365; C04B2237/38; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2913; Y10T428/2918; Y10T428/292; Y10T428/2933; Y10T428/2938; Y10T428/294; Y10T428/2958; Y10T442/00; Y10T442/20; Y10T442/2926; Y10T442/2975
Claims Analysis
Total Claims: 63
Claim 1
Independent Claim
80 words
A process for forming ceramic composite articles, said process comprising: (a) introducing a ceramic precursor material onto a reinforcement fabric substrate; (b) curing the ceramic precursor; (c) converting the cured ceramic precursor material to a ceramic matrix layer by pyrolysis in an inert atmosphere at a pressure below about 50 psi; (d) applying a refractory interface layer over the converted ceramic matrix layer; and (e) densifying the article by repeating steps (a) through (d) until a desired density is achieved.
Claim 2
Dependent Claim
80 words
A process for forming ceramic composite articles, said process comprising: (a) introducing a ceramic precursor material onto a reinforcement fabric substrate; (b) curing the ceramic precursor; (c) converting the cured ceramic precursor material to a ceramic matrix layer by pyrolysis in an inert atmosphere at a pressure below about 50 psi; (d) applying a refractory interface layer over the converted ceramic matrix layer; and (e) densifying the article by repeating steps (a) through (d) until a desired density is achieved.
Claim 3
Dependent Claim
23 words
A process as in claim 1, wherein the refractory interface layer has a thickness in the range from about 0.1 to 3.0 μm.
Claim 4
Dependent Claim
29 words
A process as in claim 1, wherein the refractory interface layer is composed of a material selected from the group consisting of carbon, a carbon-ceramic mixture, and a metal.
Claim 5
Dependent Claim
31 words
A process as in claim 3, wherein the carbon refractory interface layer is applied by coating the ceramic matrix with an organic polymer and pyrolytically converting the organic polymer to carbon.
Claim 6
Dependent Claim
17 words
A process as in claim 3, wherein the carbon refractory interface layer is applied by vapor deposition.
Claim 7
Dependent Claim
22 words
A process as in claim 3, wherein the carbon-ceramic mixture refractory layer is applied by vapor co-deposition of carbon and the ceramic.
Claim 8
Dependent Claim
17 words
A process as in claim 3, wherein the metal refractory interface layer is applied by electroless plating.
Claim 9
Dependent Claim
27 words
A process as in claim 1, wherein a refractory interface layer is applied over the ceramic matrix layer prior to initial introduction of the ceramic precursor material.
Claim 10
Dependent Claim
27 words
A process as in claim 1, wherein the ceramic precursor material is an organometallic substance selected from the group consisting of polycarbosilanes, alumina organometallics, and mullite organometallics.
Claim 11
Dependent Claim
32 words
A process as in claim 1, wherein the ceramic precursor material is a liquid organometallic substance including a ceramic powder filler in an amount from about 10 to 50 percent by volume.
Claim 12
Dependent Claim
28 words
A process as in claim 10, wherein the ceramic powder filler is selected from the group consisting of alumina, silicon dioxide, boron nitride, silicon nitride, and silicon carbide.
Claim 13
Dependent Claim
21 words
A process as in claim 11, wherein the ceramic precursor material is a liquid polycarbosilane including a silicon carbide powder filler.
Claim 14
Dependent Claim
49 words
An improved process for forming ceramic composite articles of the type wherein a plurality of ceramic matrix layers are formed over a reinforcement fabric substrate, said improvement comprising applying a refractory interface layer between successive ceramic reinforcement layers, wherein there are at least two such successive ceramic reinforcement layers.
Claim 15
Dependent Claim
49 words
An improved process for forming ceramic composite articles of the type wherein a plurality of ceramic matrix layers are formed over a reinforcement fabric substrate, said improvement comprising applying a refractory interface layer between successive ceramic reinforcement layers, wherein there are at least two such successive ceramic reinforcement layers.
Claim 16
Dependent Claim
24 words
An improved process as in claim 13, wherein the refractory interface layers have a thickness in the range from about 0.1 to 3.0 μm.
Claim 17
Dependent Claim
30 words
An improved process as in claim 13, wherein the refractory interface layers are composed of a material selected from the group consisting of carbon, a carbon-ceramic mixture, and a metal.
Claim 18
Dependent Claim
32 words
An improved process as in claim 15, wherein the carbon refractory interface layer is applied by coating the ceramic matrix with an organic polymer and pyrolytically converting the organic polymer to carbon.
Claim 19
Dependent Claim
38 words
An improved method as in claim 15, wherein the carbon-ceramic refractory interface layer is applied by coating with a dilute solution of a liquid containing an organometallic or ceramic material, curing the liquid, and pyrolizing the cured liquid.
Claim 20
Dependent Claim
17 words
An improved process as in claim 15, wherein the refractory interface layer is applied by vapor deposition.
Claim 21
Dependent Claim
23 words
An improved process as in claim 15, wherein the carbon-ceramic mixture refractory layer is applied by vapor co-deposition of carbon and the ceramic.
Claim 22
Dependent Claim
18 words
An improved process as in claim 15, wherein the metal refractory interface layer is applied by electroless plating.
Claim 23
Dependent Claim
36 words
A ceramic composite article comprising a reinforcement fabric, a plurality of ceramic matrix layers formed over the reinforcement fabric, and a refractory interface layer between at least some of the successive pairs of ceramic matrix layers.
Claim 24
Dependent Claim
36 words
A ceramic composite article comprising a reinforcement fabric, a plurality of ceramic matrix layers formed over the reinforcement fabric, and a refractory interface layer between at least some of the successive pairs of ceramic matrix layers.
Claim 25
Dependent Claim
32 words
A ceramic composite article as in claim 21, wherein the reinforcement fabric is composed of a material selected from the group consisting of carbon, alumina, silicon dioxide, boron nitride, and silicon carbide.
Claim 26
Dependent Claim
36 words
A ceramic composite article as in claim 21, wherein the ceramic matrix layers are composed of a material selected from the group consisting of carbon, alumina, silicon dioxide, boron nitride, silicon carbide, titanium, oxide, and mullite.
Claim 27
Dependent Claim
25 words
A ceramic composite article as in claim 21, wherein the refractory interface layer has a thickness in the range from about 0.1 to 3.0 μm.
Claim 28
Dependent Claim
31 words
A ceramic composite article as in claim 21, wherein the refractory interface layer is composed of a material selected from the group consisting of carbon, a carbon-ceramic mixture, and a metal.
Claim 29
Dependent Claim
24 words
A ceramic composite article as in claim 21, further comprising a refractory interface layer between the reinforcement fabric and the first ceramic matrix layer.
Claim 30
Dependent Claim
11 words
A ceramic composite article formed by the process of claim 1.
Claim 31
Dependent Claim
11 words
A ceramic composite article formed by the process of claim 13.
Claim 32
Dependent Claim
50 words
A process for forming ceramic composite articles, said process comprising: introducing a liquid polycarbosilane onto a reinforcement fabric substrate; curing the polycarbosilane at an elevated temperature under non-oxidizing conditions; and converting the cured polycarbosilane to silicon carbide by pyrolysis in an inert atmosphere at a pressure below about 50 psi.
Claim 33
Dependent Claim
50 words
A process for forming ceramic composite articles, said process comprising: introducing a liquid polycarbosilane onto a reinforcement fabric substrate; curing the polycarbosilane at an elevated temperature under non-oxidizing conditions; and converting the cured polycarbosilane to silicon carbide by pyrolysis in an inert atmosphere at a pressure below about 50 psi.
Claim 34
Dependent Claim
26 words
A process as in claim 29, wherein the liquid polycarbosilane includes a ceramic powder filler in an amount from about 10 to 50 percent by volume.
Claim 35
Dependent Claim
28 words
A process as in claim 30, wherein the ceramic powder filler is selected from the group consisting of alumina, silicon dioxide, boron nitride, silicon nitride, and silicon carbide.
Claim 36
Dependent Claim
27 words
A process as in claim 29, wherein the liquid polycarbosilane is introduced by immersion of the reinforcement fabric or by extrusion and pressing into the reinforcement fabric.
Claim 37
Dependent Claim
18 words
A process as in claim 29, wherein the liquid polycarbosilane is introduced by manual application of successive layers.
Claim 38
Dependent Claim
35 words
A process as in claim 29, wherein the polycarbosilane is cured at a temperature in the range from about 150° C. to 250° C. for a time period of from about 1 to 10 hours.
Claim 39
Dependent Claim
17 words
A process as in claim 34, wherein the polycarbosilane is degassed under a vacuum prior to curing.
Claim 40
Dependent Claim
83 words
A process as in claim 29, wherein the pyrolysis step includes heating the cured polycarbosilane at from about 200° C. to 350° C. for a period of from about 1 to 5 hours, thereafter increasing the temperature at a rate of from about 5° C./hour to 10° C./hour to a temperature of about 400° C., and thereafter increasing the temperature at a rate of from about 35° C./hour to 70° C./hour to a final temperature of from about 800° C. to 1600° C.
Claim 41
Dependent Claim
23 words
A process as in claim 36, wherein the final temperature is below about 1200° C. and the silicon carbide is amorphous in nature.
Claim 42
Dependent Claim
23 words
A process as in claim 36, wherein the final temperature is above about 1200° C. and the silicon carbide is crystalline in nature.
Claim 43
Dependent Claim
79 words
A process for forming ceramic composite articles, said process comprising: (a) forming a refractory interface layer on a reinforcement fabric; (b) introducing a liquid polycarbosilane onto the reinforcement fabric over the refractory interface layer; (c) curing the polycarbosilane at an elevated temperature under non-oxidizing conditions; (d) converting the cured polycarbosilane to silicon carbide by pyrolysis at a temperature below about 50 psi; and (e) densifying the article by repeating steps (a) through (d) until a desired density is achieved.
Claim 44
Dependent Claim
79 words
A process for forming ceramic composite articles, said process comprising: (a) forming a refractory interface layer on a reinforcement fabric; (b) introducing a liquid polycarbosilane onto the reinforcement fabric over the refractory interface layer; (c) curing the polycarbosilane at an elevated temperature under non-oxidizing conditions; (d) converting the cured polycarbosilane to silicon carbide by pyrolysis at a temperature below about 50 psi; and (e) densifying the article by repeating steps (a) through (d) until a desired density is achieved.
Claim 45
Dependent Claim
46 words
A process as in claim 39, wherein the refractory interface layer is formed by chemical vapor deposition of a material selected from the group consisting of carbon, boron nitride, alumina, silicon dioxide, and silicon carbide to a thickness in the range from about 0.1 to 3μm.
Claim 46
Dependent Claim
34 words
A process as in claim 39, wherein the refractory interface layer is formed by applying an organic precursor and pyrolyzing the precursor to form a carbon layer in the range from 0.1 to 3μm.
Claim 47
Dependent Claim
26 words
A process as in claim 39, wherein the liquid polycarbosilane includes a ceramic powder filler in an amount from about 10 to 50 percent by volume.
Claim 48
Dependent Claim
27 words
A process as in claim 42, wherein the ceramic powder filler is selected from the group consisting of alumina, silicon dioxide, boron nitride, carbon and silicon carbide.
Claim 49
Dependent Claim
27 words
A process as in claim 39, wherein the liquid polycarbosilane is introduced by immersion of the reinforcement fabric or by extrusion and pressing into the reinforcement fabric.
Claim 50
Dependent Claim
18 words
A process as in claim 39, wherein the liquid polycarbosilane is introduced by manual application of successive layers.
Claim 51
Dependent Claim
35 words
A process as in claim 39, wherein the polycarbosilane is cured at a temperature in the range from about 150° C. to 250° C. for a time period of from about 2 to 10 hours.
Claim 52
Dependent Claim
17 words
A process as in claim 46, wherein the polycarbosilane is degassed under a vacuum prior to curing.
Claim 53
Dependent Claim
83 words
A process as in claim 39, wherein the pyrolysis step includes heating the cured polycarbosilane at from about 200° C. to 350° C. for a period of from about 1 to 5 hours, thereafter increasing the temperature at a rate of from about 5° C./hour to 10° C./hour to a temperature of about 400° C., and thereafter increasing the temperature at a rate of from about 35° C./hour to 70° C./hour to a final temperature of from about 800° C. to 1600° C.
Claim 54
Dependent Claim
23 words
A process as in claim 48, wherein the final temperature is below about 1200° C. and the silicon carbide is amorphous in nature.
Claim 55
Dependent Claim
23 words
A process as in claim 48, wherein the final temperture is above about 1200° C. and the silicon carbide is crystalline in nature.
Claim 56
Dependent Claim
29 words
A ceramic composite article comprising a reinforcement fabric and a silicon carbide matrix, wherein the silicon carbide matrix is characterized by alternate silicon carbide layers and refractory interface layers.
Claim 57
Dependent Claim
29 words
A ceramic composite article comprising a reinforcement fabric and a silicon carbide matrix, wherein the silicon carbide matrix is characterized by alternate silicon carbide layers and refractory interface layers.
Claim 58
Dependent Claim
33 words
A ceramic composite article as in claim 51, wherein the reinforcement fabric substrate is composed of a material selected from the group consisting of carbon, alumina, silicon dioxide, boron nitride, and silicon carbide.
Claim 59
Dependent Claim
22 words
A ceramic composite article as in claim 51, wherein the silicon carbide layers were formed by curing and converting a liquid polycarbosilane.
Claim 60
Dependent Claim
36 words
A ceramic composite article as in claim 51, wherein the refractory interface layers were formed by chemical vapor deposition of a material selected from the group consisting of alumina, silicon dioxide, boron nitride, and silicon carbide.
Claim 61
Dependent Claim
25 words
A ceramic composite article as in claim 51, wherein the refractory interface layers were formed by pyrolysis of an organic layer applied to the article.
Claim 62
Dependent Claim
11 words
A ceramic composite article produced by the process of claim 29.
Claim 63
Dependent Claim
11 words
A ceramic composite article produced by the process of claim 39.
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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) | 1992-06-05 | 1992-12-05 | 1993-06-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-06-05 | 1996-12-05 | 1997-06-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-06-05 | 2000-12-05 | 2001-06-06 | $7700.00 | Window Closed / Lapsed |