US4476916A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of casting metal matrix composite in ceramic shell mold
Assignee: EIDP Inc
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Filing: 1981-07-27
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Granted: 1984-10-16
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Expires: 2001-07-27
Abstract
Abstract Method for investment casting of metal matrix composites by vacuum infiltration using a ceramic mold formed directly on the pattern.
Inventors
- 👤 Henry J. Nusbaum
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 00:50
CPC Classifications
C; C22; C22C; C22C47/00; C22C47/02; C22C47/025; B; B22; B22C; B22C13/00; B22C13/08; B22D; B22D19/00; B22D19/02; C22C47/06; C22C47/08; B22F; B22F2998/00
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
195 words
A method for making an investment cast, fiber reinforced metal matrix composite in a ceramic mold comprising forming a pattern of the composite, said pattern comprising a fiber array impregnated with a fugitive material and provided with conduits at locations to permit mold evacuation and mold filling, coating the pattern with a ceramic material that is not readily wetted by the metal to be cast when the metal is in the molten state, applying a plurality of additional coatings of a slurry of ceramic particles to the pattern to form a ceramic mold around the pattern, each of said coatings being dried after application, applying a coating of a ceramic sealant, forming a cavity within the mold by treating the pattern to remove the fugitive material, said fiber array remaining substantially in place within the mold cavity, firing the ceramic sealant, heating the mold to a temperature above the melting point of the matrix metal, introducing molten metal through a conduit into the mold cavity while applying a vacuum to the mold cavity through another conduit, infiltrating the fiber array with the molten metal, cooling the ceramic mold and removing it from the cast composite.
Claim 2
Independent Claim
195 words
A method for making an investment cast, fiber reinforced metal matrix composite in a ceramic mold comprising forming a pattern of the composite, said pattern comprising a fiber array impregnated with a fugitive material and provided with conduits at locations to permit mold evacuation and mold filling, coating the pattern with a ceramic material that is not readily wetted by the metal to be cast when the metal is in the molten state, applying a plurality of additional coatings of a slurry of ceramic particles to the pattern to form a ceramic mold around the pattern, each of said coatings being dried after application, applying a coating of a ceramic sealant, forming a cavity within the mold by treating the pattern to remove the fugitive material, said fiber array remaining substantially in place within the mold cavity, firing the ceramic sealant, heating the mold to a temperature above the melting point of the matrix metal, introducing molten metal through a conduit into the mold cavity while applying a vacuum to the mold cavity through another conduit, infiltrating the fiber array with the molten metal, cooling the ceramic mold and removing it from the cast composite.
Claim 3
Dependent Claim
18 words
The method of claim 1 wherein the coating that is first applied to the pattern is boron nitride.
Claim 4
Dependent Claim
27 words
The method of claim 1 wherein at least some of the applications of slurry are followed by application of a granular refractory material to the undried surface.
Claim 5
Dependent Claim
19 words
The method of claim 1 wherein the ceramic sealant is applied to the outer surface of the ceramic mold.
Claim 6
Dependent Claim
30 words
The method of claim 1 wherein introduction of the molten metal into the mold cavity is achieved by vacuum in the mold assisted by pressure applied to the molten metal.
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) | 1987-10-16 | 1988-04-16 | 1988-10-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-10-16 | 1992-04-16 | 1992-10-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-10-16 | 1996-04-16 | 1996-10-16 | $7700.00 | Window Closed / Lapsed |