US4515847A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Erosion-resistant nosetip construction
Assignee: United States Department of the Air Force
•
Filing: 1984-08-22
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Granted: 1985-05-07
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Expires: 2004-08-22
Abstract
Abstract A pierced fabric carbon-carbon structure is selectively loaded with a particulate material to provide resistance to erosion.
Inventors
- 👤 Arthur R. Taverna
- 👤 Warren S. Thompson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 18:36
CPC Classifications
B; B32; B32B; B32B5/00; B32B5/22; B32B5/24; B32B5/28; B32B5/26; B32B38/00; B32B38/08; B32B5/02; B32B5/024; B64; B64G; B64G1/00; B64G1/22; B64G1/52; B64G1/58; B32B2260/00; B32B2260/02; B32B2260/021; B32B2307/00; B32B2307/30; B32B2307/306; B32B2307/70; B32B2307/714; B32B2313/00; B32B2313/04; Y; Y10; Y10S; Y10S428/00; Y10S428/902; Y10T; Y10T428/00; Y10T428/24; Y10T428/24058; Y10T428/24074; Y10T428/24124; Y10T428/24802; Y10T428/2481; Y10T428/24893; Y10T428/249921; Y10T428/249923; Y10T428/29; Y10T428/2913; Y10T428/2918; Y10T428/292; Y10T428/30
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
121 words
In a process for fabricating a reentry carbon-carbon nosetip structure comprising the steps of: (a) stacking a plurality of layers of X-Y woven fabric; (b) piercing said stack of layers of woven fabric in the Z direction with a plurality of rigidized carbon rods to form a preform; (c) impregnating said preform with a material convertable to carbon by heat treatment; (d) carbonizing the impregnated preform; (e) graphitizing the carbonized preform; (f) repeating steps (c) through (e) to achieve a desired bulk density; and (g) machining the resulting densified composite structure to a desired configuration; the improvement comprising selectively loading the said layers of woven fabric with a heat-resisting particulate material to provide a desired ablative performance in said nosetip structure.
Claim 2
Dependent Claim
121 words
In a process for fabricating a reentry carbon-carbon nosetip structure comprising the steps of: (a) stacking a plurality of layers of X-Y woven fabric; (b) piercing said stack of layers of woven fabric in the Z direction with a plurality of rigidized carbon rods to form a preform; (c) impregnating said preform with a material convertable to carbon by heat treatment; (d) carbonizing the impregnated preform; (e) graphitizing the carbonized preform; (f) repeating steps (c) through (e) to achieve a desired bulk density; and (g) machining the resulting densified composite structure to a desired configuration; the improvement comprising selectively loading the said layers of woven fabric with a heat-resisting particulate material to provide a desired ablative performance in said nosetip structure.
Claim 3
Dependent Claim
51 words
The process of claim 1 wherein a first portion of said plurality of fabric layers is loaded with said particulate material and a second portion of said fabric layers is not loaded, and wherein the loaded pattern in said loaded layers is less than the full area of each fabric layer.
Claim 4
Dependent Claim
13 words
The process of claim 2 wherein said loading pattern is a circular spot.
Claim 5
Dependent Claim
20 words
The process of claim 3 wherein all the fabric layers of said first portion have a substantially identical loading pattern.
Claim 6
Dependent Claim
64 words
The process of claim 3 wherein said first portion is further divided into subportions and wherein successive subportions have circular spots of decreasing diameter wherein the subportion furthest removed from said second portion comprises a circular spot of relatively large diameter and wherein the subportions therebetween comprise circular spots of increasing diameter, whereby the resulting densified composite has, in cross-section a substantailly conically-loaded portion.
Claim 7
Dependent Claim
28 words
The process of claim 1 wherein said heat-resisting particulate material is selected from the group consisting of silicon dioxide, silicon nitride, silicon carbide, titanium carbide and tantalum carbide.
Claim 8
Dependent Claim
12 words
The process of claim 4 wherein said particulate material is tantalum carbide.
Claim 9
Dependent Claim
49 words
A mutually orthogonal three-directional reinforcement structure for a composite material which comprises a plurality of layers of X-Y woven fabric pierced by a plurality of rigid carbon rods in the Z direction, wherein at least a portion of the said fabric layers is loaded with a heat-resisting particulate material.
Claim 10
Dependent Claim
49 words
A mutually orthogonal three-directional reinforcement structure for a composite material which comprises a plurality of layers of X-Y woven fabric pierced by a plurality of rigid carbon rods in the Z direction, wherein at least a portion of the said fabric layers is loaded with a heat-resisting particulate material.
Claim 11
Dependent Claim
49 words
The structure of claim 8 wherein a first portion of said fabric layers is loaded with said particulate material and a second portion of said fabric layers is not loaded, and wherein the loaded pattern in said loaded layers is less than the full area of each fabric layer.
Claim 12
Dependent Claim
13 words
The structure of claim 9 wherein said loading pattern is a circular spot.
Claim 13
Dependent Claim
20 words
The structure of claim 10 wherein all the fabric layers of said first portion have a substantially identical loading pattern.
Claim 14
Dependent Claim
64 words
The structure of claim 9 wherein said first portion is further divided into subportions and wherein successive subportions have circular spots of decreasing diameter wherein the subportion furthest removed from said second portion comprises a circular spot of relatively large diameter and wherein the subportions therebetween comprise circular spots of increasing diameter, whereby the resulting densified composite has, in cross-section a substantially conically-loaded pattern.
References Cited (Backward Citations)
US3573123A
Cited
US3826707A
Cited
US4168337A
Cited
US4257835A
Cited
US4328272A
Cited
US4318948A
Cited
US4392624A
Cited
US4400421A
Cited
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1988-05-06 | 1988-11-05 | 1989-05-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-05-06 | 1992-11-05 | 1993-05-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-05-06 | 1996-11-05 | 1997-05-07 | $7700.00 | Window Closed / Lapsed |