Claims
- 1. A method for forming a metal matrix composite within a mold of investment material comprising the steps of:
- forming a preform mixture of liquid flow medium, binding agent and reinforcement material into the desired shape of said metal matrix composite;
- allowing the preform mixture to solidify into said desired shape;
- encasing the preform mixture within a container of investment material;
- heating said preform mixture such that any water evaporates and the flow medium is removed;
- sintering the remaining reinforcement material and binder agent to form a solid preform;
- disposing molten metal on top of the solid preform within the container such that the molten metal forms a seal with the container;
- pressurizing the molten metal such that it is forced into said preform;
- solidifying said molten metal to form said metal matrix composite in the shape of said preform; and
- removing said investment material from the metal matrix composite.
- 2. A method as described in claim 1 including before the encasing step, the step of attaching a plurality of preform mixtures to a sprue system for the function of casting a plurality of metal matrix composites during the same process.
- 3. A method as described in claim 1 wherein the encasing step includes the step of coating the solidified preform mixture to form the container.
- 4. A method as described in claim 3 wherein the step of coating includes the step of coating the solidified preform mixture with a slurry of investment material to form the container.
- 5. A method as described in claim 4 wherein the slurry of investment material is refractory material.
- 6. A method as described in claim 5 wherein the refractory material is ceramic.
- 7. A method as described in claim 2 wherein the encasing step includes the step of coating the solidified preform mixture to form the container.
- 8. A method as described in claim 7 wherein the step of coating includes the step of coating the solidified preform mixture with a slurry of investment material to form the container.
- 9. A method as described in claim 8 wherein the slurry of investment material is refractory material.
- 10. A method as described in claim 9 wherein the refractory material is ceramic.
- 11. A method for forming a metal matrix composite within a mold of investment material comprising the steps of:
- connecting a preform, which was previously prepared for infiltration of molten material and having a binding agent, to a sprue system;
- encasing the preform and sprue system within a nonporous container of investment material;
- melting out said sprue system to form piping which allows metal to flow to said preform;
- sintering said preform with said binding agent therein to form a solid preform;
- disposing molten metal on top of the preform within the container such that the molten metal forms a seal with the container;
- pressurizing the molten metal such that it is forced through said piping and into said solid preform;
- solidifying said molten metal to form a metal matrix composite in the shape of said solid preform; and
- removing said investment material from metal matrix composite.
- 12. A method as described in claim 11 wherein the encasing step includes the step of coating the solidified preform mixture to form the container.
- 13. A method as described in claim 12 wherein the step of coating includes the step of coating the solidified preform mixture with a slurry of investment material to form the container.
- 14. A method as described in claim 13 wherein the slurry of investment material is refractory material.
- 15. A method as described in claim 14 wherein the refractory material is ceramic.
- 16. A method as described in claim 11 including before the encasing step, the step of attaching a plurality of preforms to a sprue system for the function of casting a plurality of metal matrix composites during the same process.
- 17. A method as described in claim 16 wherein the encasing step includes the step of coating the solidified preform mixture to form the container.
- 18. A method as described in claim 17 wherein the step of coating includes the step of coating the solidified preform mixture with a slurry of investment material to form the container.
- 19. A method as described in claim 18 wherein the slurry of investment material is refractory material.
- 20. A method as described in claim 19 wherein the refractory material is ceramic.
Parent Case Info
This is a continuation of copending application Ser. No. 07/594,303 filed on Oct. 9, 1990, now U.S. Pat. No. 5,113,925.
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Date |
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4109699 |
Miller et al. |
Aug 1978 |
|
4365997 |
Jachowski et al. |
Dec 1982 |
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4476916 |
Nusbaum |
Oct 1984 |
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Foreign Referenced Citations (3)
Number |
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58-29564 |
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Continuations (1)
|
Number |
Date |
Country |
Parent |
594303 |
Oct 1990 |
|